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ffmpeg / libavcodec / vp8.c @ 968570d6

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1
/**
2
 * VP8 compatible video decoder
3
 *
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 * Copyright (C) 2010 David Conrad
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 * Copyright (C) 2010 Ronald S. Bultje
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 *
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 * This file is part of FFmpeg.
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 *
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 * FFmpeg is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * FFmpeg is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with FFmpeg; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
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#include "avcodec.h"
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#include "vp56.h"
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#include "vp8data.h"
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#include "vp8dsp.h"
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#include "h264pred.h"
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#include "rectangle.h"
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typedef struct {
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    uint8_t filter_level;
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    uint8_t inner_limit;
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} VP8FilterStrength;
35

    
36
typedef struct {
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    uint8_t segment;
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    uint8_t skip;
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    // todo: make it possible to check for at least (i4x4 or split_mv)
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    // in one op. are others needed?
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    uint8_t mode;
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    uint8_t ref_frame;
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    uint8_t partitioning;
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    VP56mv mv;
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    VP56mv bmv[16];
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} VP8Macroblock;
47

    
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typedef struct {
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    AVCodecContext *avctx;
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    DSPContext dsp;
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    VP8DSPContext vp8dsp;
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    H264PredContext hpc;
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    vp8_mc_func put_pixels_tab[3][3][3];
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    AVFrame frames[4];
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    AVFrame *framep[4];
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    uint8_t *edge_emu_buffer;
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    VP56RangeCoder c;   ///< header context, includes mb modes and motion vectors
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    int profile;
59

    
60
    int mb_width;   /* number of horizontal MB */
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    int mb_height;  /* number of vertical MB */
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    int linesize;
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    int uvlinesize;
64

    
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    int keyframe;
66
    int invisible;
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    int update_last;    ///< update VP56_FRAME_PREVIOUS with the current one
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    int update_golden;  ///< VP56_FRAME_NONE if not updated, or which frame to copy if so
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    int update_altref;
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    int deblock_filter;
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    /**
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     * If this flag is not set, all the probability updates
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     * are discarded after this frame is decoded.
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     */
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    int update_probabilities;
77

    
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    /**
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     * All coefficients are contained in separate arith coding contexts.
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     * There can be 1, 2, 4, or 8 of these after the header context.
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     */
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    int num_coeff_partitions;
83
    VP56RangeCoder coeff_partition[8];
84

    
85
    VP8Macroblock *macroblocks;
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    VP8Macroblock *macroblocks_base;
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    VP8FilterStrength *filter_strength;
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    int mb_stride;
89

    
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    uint8_t *intra4x4_pred_mode;
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    uint8_t *intra4x4_pred_mode_base;
92
    int b4_stride;
93

    
94
    /**
95
     * Cache of the top row needed for intra prediction
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     * 16 for luma, 8 for each chroma plane
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     */
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    uint8_t (*top_border)[16+8+8];
99

    
100
    /**
101
     * For coeff decode, we need to know whether the above block had non-zero
102
     * coefficients. This means for each macroblock, we need data for 4 luma
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     * blocks, 2 u blocks, 2 v blocks, and the luma dc block, for a total of 9
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     * per macroblock. We keep the last row in top_nnz.
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     */
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    uint8_t (*top_nnz)[9];
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    DECLARE_ALIGNED(8, uint8_t, left_nnz)[9];
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    /**
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     * This is the index plus one of the last non-zero coeff
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     * for each of the blocks in the current macroblock.
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     * So, 0 -> no coeffs
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     *     1 -> dc-only (special transform)
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     *     2+-> full transform
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     */
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    DECLARE_ALIGNED(16, uint8_t, non_zero_count_cache)[6][4];
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    DECLARE_ALIGNED(16, DCTELEM, block)[6][4][16];
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    uint8_t intra4x4_pred_mode_mb[16];
119

    
120
    int chroma_pred_mode;    ///< 8x8c pred mode of the current macroblock
121

    
122
    int mbskip_enabled;
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    int sign_bias[4]; ///< one state [0, 1] per ref frame type
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125
    /**
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     * Base parameters for segmentation, i.e. per-macroblock parameters.
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     * These must be kept unchanged even if segmentation is not used for
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     * a frame, since the values persist between interframes.
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     */
130
    struct {
131
        int enabled;
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        int absolute_vals;
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        int update_map;
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        int8_t base_quant[4];
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        int8_t filter_level[4];     ///< base loop filter level
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    } segmentation;
137

    
138
    /**
139
     * Macroblocks can have one of 4 different quants in a frame when
140
     * segmentation is enabled.
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     * If segmentation is disabled, only the first segment's values are used.
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     */
143
    struct {
144
        // [0] - DC qmul  [1] - AC qmul
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        int16_t luma_qmul[2];
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        int16_t luma_dc_qmul[2];    ///< luma dc-only block quant
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        int16_t chroma_qmul[2];
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    } qmat[4];
149

    
150
    struct {
151
        int simple;
152
        int level;
153
        int sharpness;
154
    } filter;
155

    
156
    struct {
157
        int enabled;    ///< whether each mb can have a different strength based on mode/ref
158

    
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        /**
160
         * filter strength adjustment for the following macroblock modes:
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         * [0] - i4x4
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         * [1] - zero mv
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         * [2] - inter modes except for zero or split mv
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         * [3] - split mv
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         *  i16x16 modes never have any adjustment
166
         */
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        int8_t mode[4];
168

    
169
        /**
170
         * filter strength adjustment for macroblocks that reference:
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         * [0] - intra / VP56_FRAME_CURRENT
172
         * [1] - VP56_FRAME_PREVIOUS
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         * [2] - VP56_FRAME_GOLDEN
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         * [3] - altref / VP56_FRAME_GOLDEN2
175
         */
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        int8_t ref[4];
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    } lf_delta;
178

    
179
    /**
180
     * These are all of the updatable probabilities for binary decisions.
181
     * They are only implictly reset on keyframes, making it quite likely
182
     * for an interframe to desync if a prior frame's header was corrupt
183
     * or missing outright!
184
     */
185
    struct {
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        uint8_t segmentid[3];
187
        uint8_t mbskip;
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        uint8_t intra;
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        uint8_t last;
190
        uint8_t golden;
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        uint8_t pred16x16[4];
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        uint8_t pred8x8c[3];
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        uint8_t token[4][8][3][NUM_DCT_TOKENS-1];
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        uint8_t mvc[2][19];
195
    } prob[2];
196
} VP8Context;
197

    
198
#define RL24(p) (AV_RL16(p) + ((p)[2] << 16))
199

    
200
static void vp8_decode_flush(AVCodecContext *avctx)
201
{
202
    VP8Context *s = avctx->priv_data;
203
    int i;
204

    
205
    for (i = 0; i < 4; i++)
206
        if (s->frames[i].data[0])
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            avctx->release_buffer(avctx, &s->frames[i]);
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    memset(s->framep, 0, sizeof(s->framep));
209

    
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    av_freep(&s->macroblocks_base);
211
    av_freep(&s->intra4x4_pred_mode_base);
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    av_freep(&s->top_nnz);
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    av_freep(&s->edge_emu_buffer);
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    av_freep(&s->top_border);
215

    
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    s->macroblocks        = NULL;
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    s->intra4x4_pred_mode = NULL;
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}
219

    
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static int update_dimensions(VP8Context *s, int width, int height)
221
{
222
    int i;
223

    
224
    if (avcodec_check_dimensions(s->avctx, width, height))
225
        return AVERROR_INVALIDDATA;
226

    
227
    vp8_decode_flush(s->avctx);
228

    
229
    avcodec_set_dimensions(s->avctx, width, height);
230

    
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    s->mb_width  = (s->avctx->coded_width +15) / 16;
232
    s->mb_height = (s->avctx->coded_height+15) / 16;
233

    
234
    // we allocate a border around the top/left of intra4x4 modes
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    // this is 4 blocks for intra4x4 to keep 4-byte alignment for fill_rectangle
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    s->mb_stride = s->mb_width+1;
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    s->b4_stride = 4*s->mb_stride;
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239
    s->macroblocks_base        = av_mallocz(s->mb_stride*(s->mb_height+1)*sizeof(*s->macroblocks));
240
    s->filter_strength         = av_mallocz(s->mb_stride*sizeof(*s->filter_strength));
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    s->intra4x4_pred_mode_base = av_mallocz(s->b4_stride*(4*s->mb_height+1));
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    s->top_nnz                 = av_mallocz(s->mb_width*sizeof(*s->top_nnz));
243
    s->top_border              = av_mallocz((s->mb_width+1)*sizeof(*s->top_border));
244

    
245
    if (!s->macroblocks_base || !s->filter_strength || !s->intra4x4_pred_mode_base || !s->top_nnz || !s->top_border)
246
        return AVERROR(ENOMEM);
247

    
248
    s->macroblocks        = s->macroblocks_base        + 1 + s->mb_stride;
249
    s->intra4x4_pred_mode = s->intra4x4_pred_mode_base + 4 + s->b4_stride;
250

    
251
    memset(s->intra4x4_pred_mode_base, DC_PRED, s->b4_stride);
252
    for (i = 0; i < 4*s->mb_height; i++)
253
        s->intra4x4_pred_mode[i*s->b4_stride-1] = DC_PRED;
254

    
255
    return 0;
256
}
257

    
258
static void parse_segment_info(VP8Context *s)
259
{
260
    VP56RangeCoder *c = &s->c;
261
    int i;
262

    
263
    s->segmentation.update_map = vp8_rac_get(c);
264

    
265
    if (vp8_rac_get(c)) { // update segment feature data
266
        s->segmentation.absolute_vals = vp8_rac_get(c);
267

    
268
        for (i = 0; i < 4; i++)
269
            s->segmentation.base_quant[i]   = vp8_rac_get_sint(c, 7);
270

    
271
        for (i = 0; i < 4; i++)
272
            s->segmentation.filter_level[i] = vp8_rac_get_sint(c, 6);
273
    }
274
    if (s->segmentation.update_map)
275
        for (i = 0; i < 3; i++)
276
            s->prob->segmentid[i] = vp8_rac_get(c) ? vp8_rac_get_uint(c, 8) : 255;
277
}
278

    
279
static void update_lf_deltas(VP8Context *s)
280
{
281
    VP56RangeCoder *c = &s->c;
282
    int i;
283

    
284
    for (i = 0; i < 4; i++)
285
        s->lf_delta.ref[i]  = vp8_rac_get_sint(c, 6);
286

    
287
    for (i = 0; i < 4; i++)
288
        s->lf_delta.mode[i] = vp8_rac_get_sint(c, 6);
289
}
290

    
291
static int setup_partitions(VP8Context *s, const uint8_t *buf, int buf_size)
292
{
293
    const uint8_t *sizes = buf;
294
    int i;
295

    
296
    s->num_coeff_partitions = 1 << vp8_rac_get_uint(&s->c, 2);
297

    
298
    buf      += 3*(s->num_coeff_partitions-1);
299
    buf_size -= 3*(s->num_coeff_partitions-1);
300
    if (buf_size < 0)
301
        return -1;
302

    
303
    for (i = 0; i < s->num_coeff_partitions-1; i++) {
304
        int size = RL24(sizes + 3*i);
305
        if (buf_size - size < 0)
306
            return -1;
307

    
308
        vp56_init_range_decoder(&s->coeff_partition[i], buf, size);
309
        buf      += size;
310
        buf_size -= size;
311
    }
312
    vp56_init_range_decoder(&s->coeff_partition[i], buf, buf_size);
313

    
314
    return 0;
315
}
316

    
317
static void get_quants(VP8Context *s)
318
{
319
    VP56RangeCoder *c = &s->c;
320
    int i, base_qi;
321

    
322
    int yac_qi     = vp8_rac_get_uint(c, 7);
323
    int ydc_delta  = vp8_rac_get_sint(c, 4);
324
    int y2dc_delta = vp8_rac_get_sint(c, 4);
325
    int y2ac_delta = vp8_rac_get_sint(c, 4);
326
    int uvdc_delta = vp8_rac_get_sint(c, 4);
327
    int uvac_delta = vp8_rac_get_sint(c, 4);
328

    
329
    for (i = 0; i < 4; i++) {
330
        if (s->segmentation.enabled) {
331
            base_qi = s->segmentation.base_quant[i];
332
            if (!s->segmentation.absolute_vals)
333
                base_qi += yac_qi;
334
        } else
335
            base_qi = yac_qi;
336

    
337
        s->qmat[i].luma_qmul[0]    =       vp8_dc_qlookup[av_clip(base_qi + ydc_delta , 0, 127)];
338
        s->qmat[i].luma_qmul[1]    =       vp8_ac_qlookup[av_clip(base_qi             , 0, 127)];
339
        s->qmat[i].luma_dc_qmul[0] =   2 * vp8_dc_qlookup[av_clip(base_qi + y2dc_delta, 0, 127)];
340
        s->qmat[i].luma_dc_qmul[1] = 155 * vp8_ac_qlookup[av_clip(base_qi + y2ac_delta, 0, 127)] / 100;
341
        s->qmat[i].chroma_qmul[0]  =       vp8_dc_qlookup[av_clip(base_qi + uvdc_delta, 0, 127)];
342
        s->qmat[i].chroma_qmul[1]  =       vp8_ac_qlookup[av_clip(base_qi + uvac_delta, 0, 127)];
343

    
344
        s->qmat[i].luma_dc_qmul[1] = FFMAX(s->qmat[i].luma_dc_qmul[1], 8);
345
        s->qmat[i].chroma_qmul[0]  = FFMIN(s->qmat[i].chroma_qmul[0], 132);
346
    }
347
}
348

    
349
/**
350
 * Determine which buffers golden and altref should be updated with after this frame.
351
 * The spec isn't clear here, so I'm going by my understanding of what libvpx does
352
 *
353
 * Intra frames update all 3 references
354
 * Inter frames update VP56_FRAME_PREVIOUS if the update_last flag is set
355
 * If the update (golden|altref) flag is set, it's updated with the current frame
356
 *      if update_last is set, and VP56_FRAME_PREVIOUS otherwise.
357
 * If the flag is not set, the number read means:
358
 *      0: no update
359
 *      1: VP56_FRAME_PREVIOUS
360
 *      2: update golden with altref, or update altref with golden
361
 */
362
static VP56Frame ref_to_update(VP8Context *s, int update, VP56Frame ref)
363
{
364
    VP56RangeCoder *c = &s->c;
365

    
366
    if (update)
367
        return VP56_FRAME_CURRENT;
368

    
369
    switch (vp8_rac_get_uint(c, 2)) {
370
    case 1:
371
        return VP56_FRAME_PREVIOUS;
372
    case 2:
373
        return (ref == VP56_FRAME_GOLDEN) ? VP56_FRAME_GOLDEN2 : VP56_FRAME_GOLDEN;
374
    }
375
    return VP56_FRAME_NONE;
376
}
377

    
378
static void update_refs(VP8Context *s)
379
{
380
    VP56RangeCoder *c = &s->c;
381

    
382
    int update_golden = vp8_rac_get(c);
383
    int update_altref = vp8_rac_get(c);
384

    
385
    s->update_golden = ref_to_update(s, update_golden, VP56_FRAME_GOLDEN);
386
    s->update_altref = ref_to_update(s, update_altref, VP56_FRAME_GOLDEN2);
387
}
388

    
389
static int decode_frame_header(VP8Context *s, const uint8_t *buf, int buf_size)
390
{
391
    VP56RangeCoder *c = &s->c;
392
    int header_size, hscale, vscale, i, j, k, l, ret;
393
    int width  = s->avctx->width;
394
    int height = s->avctx->height;
395

    
396
    s->keyframe  = !(buf[0] & 1);
397
    s->profile   =  (buf[0]>>1) & 7;
398
    s->invisible = !(buf[0] & 0x10);
399
    header_size  = RL24(buf) >> 5;
400
    buf      += 3;
401
    buf_size -= 3;
402

    
403
    if (s->profile > 3)
404
        av_log(s->avctx, AV_LOG_WARNING, "Unknown profile %d\n", s->profile);
405

    
406
    if (!s->profile)
407
        memcpy(s->put_pixels_tab, s->vp8dsp.put_vp8_epel_pixels_tab, sizeof(s->put_pixels_tab));
408
    else    // profile 1-3 use bilinear, 4+ aren't defined so whatever
409
        memcpy(s->put_pixels_tab, s->vp8dsp.put_vp8_bilinear_pixels_tab, sizeof(s->put_pixels_tab));
410

    
411
    if (header_size > buf_size - 7*s->keyframe) {
412
        av_log(s->avctx, AV_LOG_ERROR, "Header size larger than data provided\n");
413
        return AVERROR_INVALIDDATA;
414
    }
415

    
416
    if (s->keyframe) {
417
        if (RL24(buf) != 0x2a019d) {
418
            av_log(s->avctx, AV_LOG_ERROR, "Invalid start code 0x%x\n", RL24(buf));
419
            return AVERROR_INVALIDDATA;
420
        }
421
        width  = AV_RL16(buf+3) & 0x3fff;
422
        height = AV_RL16(buf+5) & 0x3fff;
423
        hscale = buf[4] >> 6;
424
        vscale = buf[6] >> 6;
425
        buf      += 7;
426
        buf_size -= 7;
427

    
428
        if (hscale || vscale)
429
            av_log_missing_feature(s->avctx, "Upscaling", 1);
430

    
431
        s->update_golden = s->update_altref = VP56_FRAME_CURRENT;
432
        memcpy(s->prob->token    , vp8_token_default_probs , sizeof(s->prob->token));
433
        memcpy(s->prob->pred16x16, vp8_pred16x16_prob_inter, sizeof(s->prob->pred16x16));
434
        memcpy(s->prob->pred8x8c , vp8_pred8x8c_prob_inter , sizeof(s->prob->pred8x8c));
435
        memcpy(s->prob->mvc      , vp8_mv_default_prob     , sizeof(s->prob->mvc));
436
        memset(&s->segmentation, 0, sizeof(s->segmentation));
437
    }
438

    
439
    if (!s->macroblocks_base || /* first frame */
440
        width != s->avctx->width || height != s->avctx->height) {
441
        if ((ret = update_dimensions(s, width, height) < 0))
442
            return ret;
443
    }
444

    
445
    vp56_init_range_decoder(c, buf, header_size);
446
    buf      += header_size;
447
    buf_size -= header_size;
448

    
449
    if (s->keyframe) {
450
        if (vp8_rac_get(c))
451
            av_log(s->avctx, AV_LOG_WARNING, "Unspecified colorspace\n");
452
        vp8_rac_get(c); // whether we can skip clamping in dsp functions
453
    }
454

    
455
    if ((s->segmentation.enabled = vp8_rac_get(c)))
456
        parse_segment_info(s);
457
    else
458
        s->segmentation.update_map = 0; // FIXME: move this to some init function?
459

    
460
    s->filter.simple    = vp8_rac_get(c);
461
    s->filter.level     = vp8_rac_get_uint(c, 6);
462
    s->filter.sharpness = vp8_rac_get_uint(c, 3);
463

    
464
    if ((s->lf_delta.enabled = vp8_rac_get(c)))
465
        if (vp8_rac_get(c))
466
            update_lf_deltas(s);
467

    
468
    if (setup_partitions(s, buf, buf_size)) {
469
        av_log(s->avctx, AV_LOG_ERROR, "Invalid partitions\n");
470
        return AVERROR_INVALIDDATA;
471
    }
472

    
473
    get_quants(s);
474

    
475
    if (!s->keyframe) {
476
        update_refs(s);
477
        s->sign_bias[VP56_FRAME_GOLDEN]               = vp8_rac_get(c);
478
        s->sign_bias[VP56_FRAME_GOLDEN2 /* altref */] = vp8_rac_get(c);
479
    }
480

    
481
    // if we aren't saving this frame's probabilities for future frames,
482
    // make a copy of the current probabilities
483
    if (!(s->update_probabilities = vp8_rac_get(c)))
484
        s->prob[1] = s->prob[0];
485

    
486
    s->update_last = s->keyframe || vp8_rac_get(c);
487

    
488
    for (i = 0; i < 4; i++)
489
        for (j = 0; j < 8; j++)
490
            for (k = 0; k < 3; k++)
491
                for (l = 0; l < NUM_DCT_TOKENS-1; l++)
492
                    if (vp56_rac_get_prob(c, vp8_token_update_probs[i][j][k][l]))
493
                        s->prob->token[i][j][k][l] = vp8_rac_get_uint(c, 8);
494

    
495
    if ((s->mbskip_enabled = vp8_rac_get(c)))
496
        s->prob->mbskip = vp8_rac_get_uint(c, 8);
497

    
498
    if (!s->keyframe) {
499
        s->prob->intra  = vp8_rac_get_uint(c, 8);
500
        s->prob->last   = vp8_rac_get_uint(c, 8);
501
        s->prob->golden = vp8_rac_get_uint(c, 8);
502

    
503
        if (vp8_rac_get(c))
504
            for (i = 0; i < 4; i++)
505
                s->prob->pred16x16[i] = vp8_rac_get_uint(c, 8);
506
        if (vp8_rac_get(c))
507
            for (i = 0; i < 3; i++)
508
                s->prob->pred8x8c[i]  = vp8_rac_get_uint(c, 8);
509

    
510
        // 17.2 MV probability update
511
        for (i = 0; i < 2; i++)
512
            for (j = 0; j < 19; j++)
513
                if (vp56_rac_get_prob(c, vp8_mv_update_prob[i][j]))
514
                    s->prob->mvc[i][j] = vp8_rac_get_nn(c);
515
    }
516

    
517
    return 0;
518
}
519

    
520
static inline void clamp_mv(VP8Context *s, VP56mv *dst, const VP56mv *src,
521
                            int mb_x, int mb_y)
522
{
523
#define MARGIN (16 << 2)
524
    dst->x = av_clip(src->x, -((mb_x << 6) + MARGIN),
525
                     ((s->mb_width  - 1 - mb_x) << 6) + MARGIN);
526
    dst->y = av_clip(src->y, -((mb_y << 6) + MARGIN),
527
                     ((s->mb_height - 1 - mb_y) << 6) + MARGIN);
528
}
529

    
530
static void find_near_mvs(VP8Context *s, VP8Macroblock *mb, int mb_x, int mb_y,
531
                          VP56mv near[2], VP56mv *best, uint8_t cnt[4])
532
{
533
    int mb_stride = s->mb_stride;
534
    VP8Macroblock *mb_edge[3] = { mb - mb_stride     /* top */,
535
                                  mb - 1             /* left */,
536
                                  mb - mb_stride - 1 /* top-left */ };
537
    enum { EDGE_TOP, EDGE_LEFT, EDGE_TOPLEFT };
538
    VP56mv near_mv[4]  = {{ 0 }};
539
    enum { CNT_ZERO, CNT_NEAREST, CNT_NEAR, CNT_SPLITMV };
540
    int idx = CNT_ZERO;
541
    int best_idx = CNT_ZERO;
542
    int cur_sign_bias = s->sign_bias[mb->ref_frame];
543
    int *sign_bias = s->sign_bias;
544

    
545
    /* Process MB on top, left and top-left */
546
    #define MV_EDGE_CHECK(n)\
547
    {\
548
        VP8Macroblock *edge = mb_edge[n];\
549
        int edge_ref = edge->ref_frame;\
550
        if (edge_ref != VP56_FRAME_CURRENT) {\
551
            uint32_t mv = AV_RN32A(&edge->mv);\
552
            if (mv) {\
553
                if (cur_sign_bias != sign_bias[edge_ref]) {\
554
                    /* SWAR negate of the values in mv. */\
555
                    mv = ((mv&0x80008000) + 0x00010001) ^ (mv&0x7fff7fff);\
556
                }\
557
                if (!n || mv != AV_RN32A(&near_mv[idx]))\
558
                    AV_WN32A(&near_mv[++idx], mv);\
559
                cnt[idx]      += 1 + (n != 2);\
560
            } else\
561
                cnt[CNT_ZERO] += 1 + (n != 2);\
562
        }\
563
    }
564
    MV_EDGE_CHECK(0)
565
    MV_EDGE_CHECK(1)
566
    MV_EDGE_CHECK(2)
567

    
568
    /* If we have three distinct MVs, merge first and last if they're the same */
569
    if (cnt[CNT_SPLITMV] && AV_RN32A(&near_mv[1+EDGE_TOP]) == AV_RN32A(&near_mv[1+EDGE_TOPLEFT]))
570
        cnt[CNT_NEAREST] += 1;
571

    
572
    cnt[CNT_SPLITMV] = ((mb_edge[EDGE_LEFT]->mode   == VP8_MVMODE_SPLIT) +
573
                        (mb_edge[EDGE_TOP]->mode    == VP8_MVMODE_SPLIT)) * 2 +
574
                       (mb_edge[EDGE_TOPLEFT]->mode == VP8_MVMODE_SPLIT);
575

    
576
    /* Swap near and nearest if necessary */
577
    if (cnt[CNT_NEAR] > cnt[CNT_NEAREST]) {
578
        FFSWAP(uint8_t,     cnt[CNT_NEAREST],     cnt[CNT_NEAR]);
579
        FFSWAP( VP56mv, near_mv[CNT_NEAREST], near_mv[CNT_NEAR]);
580
    }
581

    
582
    /* Choose the best mv out of 0,0 and the nearest mv */
583
    if (cnt[CNT_NEAREST] >= cnt[CNT_ZERO])
584
        best_idx = CNT_NEAREST;
585

    
586
    clamp_mv(s, best, &near_mv[best_idx], mb_x, mb_y);
587
    near[0] = near_mv[CNT_NEAREST];
588
    near[1] = near_mv[CNT_NEAR];
589
}
590

    
591
/**
592
 * Motion vector coding, 17.1.
593
 */
594
static int read_mv_component(VP56RangeCoder *c, const uint8_t *p)
595
{
596
    int x = 0;
597

    
598
    if (vp56_rac_get_prob(c, p[0])) {
599
        int i;
600

    
601
        for (i = 0; i < 3; i++)
602
            x += vp56_rac_get_prob(c, p[9 + i]) << i;
603
        for (i = 9; i > 3; i--)
604
            x += vp56_rac_get_prob(c, p[9 + i]) << i;
605
        if (!(x & 0xFFF0) || vp56_rac_get_prob(c, p[12]))
606
            x += 8;
607
    } else
608
        x = vp8_rac_get_tree(c, vp8_small_mvtree, &p[2]);
609

    
610
    return (x && vp56_rac_get_prob(c, p[1])) ? -x : x;
611
}
612

    
613
static const uint8_t *get_submv_prob(uint32_t left, uint32_t top)
614
{
615
    if (left == top)
616
        return vp8_submv_prob[4-!!left];
617
    if (!top)
618
        return vp8_submv_prob[2];
619
    return vp8_submv_prob[1-!!left];
620
}
621

    
622
/**
623
 * Split motion vector prediction, 16.4.
624
 * @returns the number of motion vectors parsed (2, 4 or 16)
625
 */
626
static int decode_splitmvs(VP8Context    *s,  VP56RangeCoder *c,
627
                            VP8Macroblock *mb, VP56mv         *base_mv)
628
{
629
    int part_idx = mb->partitioning =
630
        vp8_rac_get_tree(c, vp8_mbsplit_tree, vp8_mbsplit_prob);
631
    int n, num = vp8_mbsplit_count[part_idx];
632
    VP8Macroblock *top_mb  = &mb[-s->mb_stride];
633
    VP8Macroblock *left_mb = &mb[-1];
634
    const uint8_t *mbsplits_left = vp8_mbsplits[left_mb->partitioning],
635
                  *mbsplits_top = vp8_mbsplits[top_mb->partitioning],
636
                  *mbsplits_cur = vp8_mbsplits[part_idx],
637
                  *firstidx = vp8_mbfirstidx[part_idx];
638
    VP56mv *top_mv   = top_mb->bmv;
639
    VP56mv *left_mv  = left_mb->bmv;
640
    VP56mv *cur_mv   = mb->bmv;
641

    
642
    for (n = 0; n < num; n++) {
643
        int k = firstidx[n];
644
        uint32_t left, above;
645
        const uint8_t *submv_prob;
646

    
647
        if (!(k & 3))
648
            left = AV_RN32A(&left_mv[mbsplits_left[k + 3]]);
649
        else
650
            left  = AV_RN32A(&cur_mv[mbsplits_cur[k - 1]]);
651
        if (k <= 3)
652
            above = AV_RN32A(&top_mv[mbsplits_top[k + 12]]);
653
        else
654
            above = AV_RN32A(&cur_mv[mbsplits_cur[k - 4]]);
655

    
656
        submv_prob = get_submv_prob(left, above);
657

    
658
        switch (vp8_rac_get_tree(c, vp8_submv_ref_tree, submv_prob)) {
659
        case VP8_SUBMVMODE_NEW4X4:
660
            mb->bmv[n].y = base_mv->y + read_mv_component(c, s->prob->mvc[0]);
661
            mb->bmv[n].x = base_mv->x + read_mv_component(c, s->prob->mvc[1]);
662
            break;
663
        case VP8_SUBMVMODE_ZERO4X4:
664
            AV_WN32A(&mb->bmv[n], 0);
665
            break;
666
        case VP8_SUBMVMODE_LEFT4X4:
667
            AV_WN32A(&mb->bmv[n], left);
668
            break;
669
        case VP8_SUBMVMODE_TOP4X4:
670
            AV_WN32A(&mb->bmv[n], above);
671
            break;
672
        }
673
    }
674

    
675
    return num;
676
}
677

    
678
static inline void decode_intra4x4_modes(VP56RangeCoder *c, uint8_t *intra4x4,
679
                                         int stride, int keyframe)
680
{
681
    int x, y, t, l, i;
682

    
683
    if (keyframe) {
684
        const uint8_t *ctx;
685
        for (y = 0; y < 4; y++) {
686
            for (x = 0; x < 4; x++) {
687
                t = intra4x4[x - stride];
688
                l = intra4x4[x - 1];
689
                ctx = vp8_pred4x4_prob_intra[t][l];
690
                intra4x4[x] = vp8_rac_get_tree(c, vp8_pred4x4_tree, ctx);
691
            }
692
            intra4x4 += stride;
693
        }
694
    } else {
695
        for (i = 0; i < 16; i++)
696
            intra4x4[i] = vp8_rac_get_tree(c, vp8_pred4x4_tree, vp8_pred4x4_prob_inter);
697
    }
698
}
699

    
700
static void decode_mb_mode(VP8Context *s, VP8Macroblock *mb, int mb_x, int mb_y,
701
                           uint8_t *intra4x4)
702
{
703
    VP56RangeCoder *c = &s->c;
704

    
705
    if (s->segmentation.update_map)
706
        mb->segment = vp8_rac_get_tree(c, vp8_segmentid_tree, s->prob->segmentid);
707

    
708
    mb->skip = s->mbskip_enabled ? vp56_rac_get_prob(c, s->prob->mbskip) : 0;
709

    
710
    if (s->keyframe) {
711
        mb->mode = vp8_rac_get_tree(c, vp8_pred16x16_tree_intra, vp8_pred16x16_prob_intra);
712

    
713
        if (mb->mode == MODE_I4x4) {
714
            decode_intra4x4_modes(c, intra4x4, s->b4_stride, 1);
715
        } else
716
            fill_rectangle(intra4x4, 4, 4, s->b4_stride, vp8_pred4x4_mode[mb->mode], 1);
717

    
718
        s->chroma_pred_mode = vp8_rac_get_tree(c, vp8_pred8x8c_tree, vp8_pred8x8c_prob_intra);
719
        mb->ref_frame = VP56_FRAME_CURRENT;
720
    } else if (vp56_rac_get_prob(c, s->prob->intra)) {
721
        VP56mv near[2], best;
722
        uint8_t cnt[4] = { 0 };
723
        uint8_t p[4];
724

    
725
        // inter MB, 16.2
726
        if (vp56_rac_get_prob(c, s->prob->last))
727
            mb->ref_frame = vp56_rac_get_prob(c, s->prob->golden) ?
728
                VP56_FRAME_GOLDEN2 /* altref */ : VP56_FRAME_GOLDEN;
729
        else
730
            mb->ref_frame = VP56_FRAME_PREVIOUS;
731

    
732
        // motion vectors, 16.3
733
        find_near_mvs(s, mb, mb_x, mb_y, near, &best, cnt);
734
        p[0] = vp8_mode_contexts[cnt[0]][0];
735
        p[1] = vp8_mode_contexts[cnt[1]][1];
736
        p[2] = vp8_mode_contexts[cnt[2]][2];
737
        p[3] = vp8_mode_contexts[cnt[3]][3];
738
        mb->mode = vp8_rac_get_tree(c, vp8_pred16x16_tree_mvinter, p);
739
        switch (mb->mode) {
740
        case VP8_MVMODE_SPLIT:
741
            mb->mv = mb->bmv[decode_splitmvs(s, c, mb, &best) - 1];
742
            break;
743
        case VP8_MVMODE_ZERO:
744
            mb->mv.x = 0;
745
            mb->mv.y = 0;
746
            break;
747
        case VP8_MVMODE_NEAREST:
748
            clamp_mv(s, &mb->mv, &near[0], mb_x, mb_y);
749
            break;
750
        case VP8_MVMODE_NEAR:
751
            clamp_mv(s, &mb->mv, &near[1], mb_x, mb_y);
752
            break;
753
        case VP8_MVMODE_NEW:
754
            mb->mv.y = best.y + read_mv_component(c, s->prob->mvc[0]);
755
            mb->mv.x = best.x + read_mv_component(c, s->prob->mvc[1]);
756
            break;
757
        }
758
        if (mb->mode != VP8_MVMODE_SPLIT) {
759
            mb->partitioning = VP8_SPLITMVMODE_NONE;
760
            mb->bmv[0] = mb->mv;
761
        }
762
    } else {
763
        // intra MB, 16.1
764
        mb->mode = vp8_rac_get_tree(c, vp8_pred16x16_tree_inter, s->prob->pred16x16);
765

    
766
        if (mb->mode == MODE_I4x4)
767
            decode_intra4x4_modes(c, intra4x4, 4, 0);
768

    
769
        s->chroma_pred_mode = vp8_rac_get_tree(c, vp8_pred8x8c_tree, s->prob->pred8x8c);
770
        mb->ref_frame = VP56_FRAME_CURRENT;
771
    }
772
}
773

    
774
/**
775
 * @param c arithmetic bitstream reader context
776
 * @param block destination for block coefficients
777
 * @param probs probabilities to use when reading trees from the bitstream
778
 * @param i initial coeff index, 0 unless a separate DC block is coded
779
 * @param zero_nhood the initial prediction context for number of surrounding
780
 *                   all-zero blocks (only left/top, so 0-2)
781
 * @param qmul array holding the dc/ac dequant factor at position 0/1
782
 * @return 0 if no coeffs were decoded
783
 *         otherwise, the index of the last coeff decoded plus one
784
 */
785
static int decode_block_coeffs(VP56RangeCoder *c, DCTELEM block[16],
786
                               uint8_t probs[8][3][NUM_DCT_TOKENS-1],
787
                               int i, int zero_nhood, int16_t qmul[2])
788
{
789
    int token, nonzero = 0;
790
    int offset = 0;
791

    
792
    for (; i < 16; i++) {
793
        token = vp8_rac_get_tree_with_offset(c, vp8_coeff_tree, probs[vp8_coeff_band[i]][zero_nhood], offset);
794

    
795
        if (token == DCT_EOB)
796
            break;
797
        else if (token >= DCT_CAT1) {
798
            int cat = token-DCT_CAT1;
799
            token = vp8_rac_get_coeff(c, vp8_dct_cat_prob[cat]);
800
            token += vp8_dct_cat_offset[cat];
801
        }
802

    
803
        // after the first token, the non-zero prediction context becomes
804
        // based on the last decoded coeff
805
        if (!token) {
806
            zero_nhood = 0;
807
            offset = 1;
808
            continue;
809
        } else if (token == 1)
810
            zero_nhood = 1;
811
        else
812
            zero_nhood = 2;
813

    
814
        // todo: full [16] qmat? load into register?
815
        block[zigzag_scan[i]] = (vp8_rac_get(c) ? -token : token) * qmul[!!i];
816
        nonzero = i+1;
817
        offset = 0;
818
    }
819
    return nonzero;
820
}
821

    
822
static void decode_mb_coeffs(VP8Context *s, VP56RangeCoder *c, VP8Macroblock *mb,
823
                             uint8_t t_nnz[9], uint8_t l_nnz[9])
824
{
825
    LOCAL_ALIGNED_16(DCTELEM, dc,[16]);
826
    int i, x, y, luma_start = 0, luma_ctx = 3;
827
    int nnz_pred, nnz, nnz_total = 0;
828
    int segment = s->segmentation.enabled ? mb->segment : 0;
829

    
830
    s->dsp.clear_blocks((DCTELEM *)s->block);
831

    
832
    if (mb->mode != MODE_I4x4 && mb->mode != VP8_MVMODE_SPLIT) {
833
        AV_ZERO128(dc);
834
        AV_ZERO128(dc+8);
835
        nnz_pred = t_nnz[8] + l_nnz[8];
836

    
837
        // decode DC values and do hadamard
838
        nnz = decode_block_coeffs(c, dc, s->prob->token[1], 0, nnz_pred,
839
                                  s->qmat[segment].luma_dc_qmul);
840
        l_nnz[8] = t_nnz[8] = !!nnz;
841
        nnz_total += nnz;
842
        s->vp8dsp.vp8_luma_dc_wht(s->block, dc);
843
        luma_start = 1;
844
        luma_ctx = 0;
845
    }
846

    
847
    // luma blocks
848
    for (y = 0; y < 4; y++)
849
        for (x = 0; x < 4; x++) {
850
            nnz_pred = l_nnz[y] + t_nnz[x];
851
            nnz = decode_block_coeffs(c, s->block[y][x], s->prob->token[luma_ctx], luma_start,
852
                                      nnz_pred, s->qmat[segment].luma_qmul);
853
            // nnz+luma_start may be one more than the actual last index, but we don't care
854
            s->non_zero_count_cache[y][x] = nnz + luma_start;
855
            t_nnz[x] = l_nnz[y] = !!nnz;
856
            nnz_total += nnz;
857
        }
858

    
859
    // chroma blocks
860
    // TODO: what to do about dimensions? 2nd dim for luma is x,
861
    // but for chroma it's (y<<1)|x
862
    for (i = 4; i < 6; i++)
863
        for (y = 0; y < 2; y++)
864
            for (x = 0; x < 2; x++) {
865
                nnz_pred = l_nnz[i+2*y] + t_nnz[i+2*x];
866
                nnz = decode_block_coeffs(c, s->block[i][(y<<1)+x], s->prob->token[2], 0,
867
                                          nnz_pred, s->qmat[segment].chroma_qmul);
868
                s->non_zero_count_cache[i][(y<<1)+x] = nnz;
869
                t_nnz[i+2*x] = l_nnz[i+2*y] = !!nnz;
870
                nnz_total += nnz;
871
            }
872

    
873
    // if there were no coded coeffs despite the macroblock not being marked skip,
874
    // we MUST not do the inner loop filter and should not do IDCT
875
    // Since skip isn't used for bitstream prediction, just manually set it.
876
    if (!nnz_total)
877
        mb->skip = 1;
878
}
879

    
880
static av_always_inline
881
void backup_mb_border(uint8_t *top_border, uint8_t *src_y, uint8_t *src_cb, uint8_t *src_cr,
882
                      int linesize, int uvlinesize, int simple)
883
{
884
    AV_COPY128(top_border, src_y + 15*linesize);
885
    if (!simple) {
886
        AV_COPY64(top_border+16, src_cb + 7*uvlinesize);
887
        AV_COPY64(top_border+24, src_cr + 7*uvlinesize);
888
    }
889
}
890

    
891
static av_always_inline
892
void xchg_mb_border(uint8_t *top_border, uint8_t *src_y, uint8_t *src_cb, uint8_t *src_cr,
893
                    int linesize, int uvlinesize, int mb_x, int mb_y, int mb_width,
894
                    int simple, int xchg)
895
{
896
    uint8_t *top_border_m1 = top_border-32;     // for TL prediction
897
    src_y  -=   linesize;
898
    src_cb -= uvlinesize;
899
    src_cr -= uvlinesize;
900

    
901
#define XCHG(a,b,xchg) do {                     \
902
        if (xchg) AV_SWAP64(b,a);               \
903
        else      AV_COPY64(b,a);               \
904
    } while (0)
905

    
906
    XCHG(top_border_m1+8, src_y-8, xchg);
907
    XCHG(top_border,      src_y,   xchg);
908
    XCHG(top_border+8,    src_y+8, 1);
909
    if (mb_x < mb_width-1)
910
        XCHG(top_border+32, src_y+16, 1);
911

    
912
    // only copy chroma for normal loop filter
913
    // or to initialize the top row to 127
914
    if (!simple || !mb_y) {
915
        XCHG(top_border_m1+16, src_cb-8, xchg);
916
        XCHG(top_border_m1+24, src_cr-8, xchg);
917
        XCHG(top_border+16,    src_cb, 1);
918
        XCHG(top_border+24,    src_cr, 1);
919
    }
920
}
921

    
922
static int check_intra_pred_mode(int mode, int mb_x, int mb_y)
923
{
924
    if (mode == DC_PRED8x8) {
925
        if (!(mb_x|mb_y))
926
            mode = DC_128_PRED8x8;
927
        else if (!mb_y)
928
            mode = LEFT_DC_PRED8x8;
929
        else if (!mb_x)
930
            mode = TOP_DC_PRED8x8;
931
    }
932
    return mode;
933
}
934

    
935
static void intra_predict(VP8Context *s, uint8_t *dst[3], VP8Macroblock *mb,
936
                          uint8_t *intra4x4, int mb_x, int mb_y)
937
{
938
    int x, y, mode, nnz, tr;
939

    
940
    // for the first row, we need to run xchg_mb_border to init the top edge to 127
941
    // otherwise, skip it if we aren't going to deblock
942
    if (s->deblock_filter || !mb_y)
943
        xchg_mb_border(s->top_border[mb_x+1], dst[0], dst[1], dst[2],
944
                       s->linesize, s->uvlinesize, mb_x, mb_y, s->mb_width,
945
                       s->filter.simple, 1);
946

    
947
    if (mb->mode < MODE_I4x4) {
948
        mode = check_intra_pred_mode(mb->mode, mb_x, mb_y);
949
        s->hpc.pred16x16[mode](dst[0], s->linesize);
950
    } else {
951
        uint8_t *ptr = dst[0];
952
        int stride = s->keyframe ? s->b4_stride : 4;
953

    
954
        // all blocks on the right edge of the macroblock use bottom edge
955
        // the top macroblock for their topright edge
956
        uint8_t *tr_right = ptr - s->linesize + 16;
957

    
958
        // if we're on the right edge of the frame, said edge is extended
959
        // from the top macroblock
960
        if (mb_x == s->mb_width-1) {
961
            tr = tr_right[-1]*0x01010101;
962
            tr_right = (uint8_t *)&tr;
963
        }
964

    
965
        for (y = 0; y < 4; y++) {
966
            uint8_t *topright = ptr + 4 - s->linesize;
967
            for (x = 0; x < 4; x++) {
968
                if (x == 3)
969
                    topright = tr_right;
970

    
971
                s->hpc.pred4x4[intra4x4[x]](ptr+4*x, topright, s->linesize);
972

    
973
                nnz = s->non_zero_count_cache[y][x];
974
                if (nnz) {
975
                    if (nnz == 1)
976
                        s->vp8dsp.vp8_idct_dc_add(ptr+4*x, s->block[y][x], s->linesize);
977
                    else
978
                        s->vp8dsp.vp8_idct_add(ptr+4*x, s->block[y][x], s->linesize);
979
                }
980
                topright += 4;
981
            }
982

    
983
            ptr   += 4*s->linesize;
984
            intra4x4 += stride;
985
        }
986
    }
987

    
988
    mode = check_intra_pred_mode(s->chroma_pred_mode, mb_x, mb_y);
989
    s->hpc.pred8x8[mode](dst[1], s->uvlinesize);
990
    s->hpc.pred8x8[mode](dst[2], s->uvlinesize);
991

    
992
    if (s->deblock_filter || !mb_y)
993
        xchg_mb_border(s->top_border[mb_x+1], dst[0], dst[1], dst[2],
994
                       s->linesize, s->uvlinesize, mb_x, mb_y, s->mb_width,
995
                       s->filter.simple, 0);
996
}
997

    
998
/**
999
 * Generic MC function.
1000
 *
1001
 * @param s VP8 decoding context
1002
 * @param luma 1 for luma (Y) planes, 0 for chroma (Cb/Cr) planes
1003
 * @param dst target buffer for block data at block position
1004
 * @param src reference picture buffer at origin (0, 0)
1005
 * @param mv motion vector (relative to block position) to get pixel data from
1006
 * @param x_off horizontal position of block from origin (0, 0)
1007
 * @param y_off vertical position of block from origin (0, 0)
1008
 * @param block_w width of block (16, 8 or 4)
1009
 * @param block_h height of block (always same as block_w)
1010
 * @param width width of src/dst plane data
1011
 * @param height height of src/dst plane data
1012
 * @param linesize size of a single line of plane data, including padding
1013
 * @param mc_func motion compensation function pointers (bilinear or sixtap MC)
1014
 */
1015
static inline void vp8_mc(VP8Context *s, int luma,
1016
                          uint8_t *dst, uint8_t *src, const VP56mv *mv,
1017
                          int x_off, int y_off, int block_w, int block_h,
1018
                          int width, int height, int linesize,
1019
                          vp8_mc_func mc_func[3][3])
1020
{
1021
    if (AV_RN32A(mv)) {
1022
        static const uint8_t idx[8] = { 0, 1, 2, 1, 2, 1, 2, 1 };
1023
        int mx = (mv->x << luma)&7, mx_idx = idx[mx];
1024
        int my = (mv->y << luma)&7, my_idx = idx[my];
1025

    
1026
        x_off += mv->x >> (3 - luma);
1027
        y_off += mv->y >> (3 - luma);
1028

    
1029
        // edge emulation
1030
        src += y_off * linesize + x_off;
1031
        if (x_off < 2 || x_off >= width  - block_w - 3 ||
1032
            y_off < 2 || y_off >= height - block_h - 3) {
1033
            ff_emulated_edge_mc(s->edge_emu_buffer, src - 2 * linesize - 2, linesize,
1034
                                block_w + 5, block_h + 5,
1035
                                x_off - 2, y_off - 2, width, height);
1036
            src = s->edge_emu_buffer + 2 + linesize * 2;
1037
        }
1038
        mc_func[my_idx][mx_idx](dst, linesize, src, linesize, block_h, mx, my);
1039
    } else
1040
        mc_func[0][0](dst, linesize, src + y_off * linesize + x_off, linesize, block_h, 0, 0);
1041
}
1042

    
1043
static inline void vp8_mc_part(VP8Context *s, uint8_t *dst[3],
1044
                               AVFrame *ref_frame, int x_off, int y_off,
1045
                               int bx_off, int by_off,
1046
                               int block_w, int block_h,
1047
                               int width, int height, VP56mv *mv)
1048
{
1049
    VP56mv uvmv = *mv;
1050

    
1051
    /* Y */
1052
    vp8_mc(s, 1, dst[0] + by_off * s->linesize + bx_off,
1053
           ref_frame->data[0], mv, x_off + bx_off, y_off + by_off,
1054
           block_w, block_h, width, height, s->linesize,
1055
           s->put_pixels_tab[block_w == 8]);
1056

    
1057
    /* U/V */
1058
    if (s->profile == 3) {
1059
        uvmv.x &= ~7;
1060
        uvmv.y &= ~7;
1061
    }
1062
    x_off   >>= 1; y_off   >>= 1;
1063
    bx_off  >>= 1; by_off  >>= 1;
1064
    width   >>= 1; height  >>= 1;
1065
    block_w >>= 1; block_h >>= 1;
1066
    vp8_mc(s, 0, dst[1] + by_off * s->uvlinesize + bx_off,
1067
           ref_frame->data[1], &uvmv, x_off + bx_off, y_off + by_off,
1068
           block_w, block_h, width, height, s->uvlinesize,
1069
           s->put_pixels_tab[1 + (block_w == 4)]);
1070
    vp8_mc(s, 0, dst[2] + by_off * s->uvlinesize + bx_off,
1071
           ref_frame->data[2], &uvmv, x_off + bx_off, y_off + by_off,
1072
           block_w, block_h, width, height, s->uvlinesize,
1073
           s->put_pixels_tab[1 + (block_w == 4)]);
1074
}
1075

    
1076
/* Fetch pixels for estimated mv 4 macroblocks ahead.
1077
 * Optimized for 64-byte cache lines.  Inspired by ffh264 prefetch_motion. */
1078
static inline void prefetch_motion(VP8Context *s, VP8Macroblock *mb, int mb_x, int mb_y, int x_off, int y_off, int ref)
1079
{
1080
    if (mb->ref_frame != VP56_FRAME_CURRENT) {
1081
        int mx = mb->mv.x + x_off + 8;
1082
        int my = mb->mv.y + y_off;
1083
        uint8_t **src= s->framep[mb->ref_frame]->data;
1084
        int off= mx + (my + (mb_x&3)*4)*s->linesize + 64;
1085
        s->dsp.prefetch(src[0]+off, s->linesize, 4);
1086
        off= (mx>>1) + ((my>>1) + (mb_x&7))*s->uvlinesize + 64;
1087
        s->dsp.prefetch(src[1]+off, src[2]-src[1], 2);
1088
    }
1089
}
1090

    
1091
/**
1092
 * Apply motion vectors to prediction buffer, chapter 18.
1093
 */
1094
static void inter_predict(VP8Context *s, uint8_t *dst[3], VP8Macroblock *mb,
1095
                          int mb_x, int mb_y)
1096
{
1097
    int x_off = mb_x << 4, y_off = mb_y << 4;
1098
    int width = 16*s->mb_width, height = 16*s->mb_height;
1099

    
1100
    prefetch_motion(s, mb, mb_x, mb_y, x_off, y_off, VP56_FRAME_PREVIOUS);
1101

    
1102
    if (mb->mode < VP8_MVMODE_SPLIT) {
1103
        vp8_mc_part(s, dst, s->framep[mb->ref_frame], x_off, y_off,
1104
                    0, 0, 16, 16, width, height, &mb->mv);
1105
    } else switch (mb->partitioning) {
1106
    case VP8_SPLITMVMODE_4x4: {
1107
        int x, y;
1108
        VP56mv uvmv;
1109

    
1110
        /* Y */
1111
        for (y = 0; y < 4; y++) {
1112
            for (x = 0; x < 4; x++) {
1113
                vp8_mc(s, 1, dst[0] + 4*y*s->linesize + x*4,
1114
                       s->framep[mb->ref_frame]->data[0], &mb->bmv[4*y + x],
1115
                       4*x + x_off, 4*y + y_off, 4, 4,
1116
                       width, height, s->linesize,
1117
                       s->put_pixels_tab[2]);
1118
            }
1119
        }
1120

    
1121
        /* U/V */
1122
        x_off >>= 1; y_off >>= 1; width >>= 1; height >>= 1;
1123
        for (y = 0; y < 2; y++) {
1124
            for (x = 0; x < 2; x++) {
1125
                uvmv.x = mb->bmv[ 2*y    * 4 + 2*x  ].x +
1126
                         mb->bmv[ 2*y    * 4 + 2*x+1].x +
1127
                         mb->bmv[(2*y+1) * 4 + 2*x  ].x +
1128
                         mb->bmv[(2*y+1) * 4 + 2*x+1].x;
1129
                uvmv.y = mb->bmv[ 2*y    * 4 + 2*x  ].y +
1130
                         mb->bmv[ 2*y    * 4 + 2*x+1].y +
1131
                         mb->bmv[(2*y+1) * 4 + 2*x  ].y +
1132
                         mb->bmv[(2*y+1) * 4 + 2*x+1].y;
1133
                uvmv.x = (uvmv.x + 2 + (uvmv.x >> (INT_BIT-1))) >> 2;
1134
                uvmv.y = (uvmv.y + 2 + (uvmv.y >> (INT_BIT-1))) >> 2;
1135
                if (s->profile == 3) {
1136
                    uvmv.x &= ~7;
1137
                    uvmv.y &= ~7;
1138
                }
1139
                vp8_mc(s, 0, dst[1] + 4*y*s->uvlinesize + x*4,
1140
                       s->framep[mb->ref_frame]->data[1], &uvmv,
1141
                       4*x + x_off, 4*y + y_off, 4, 4,
1142
                       width, height, s->uvlinesize,
1143
                       s->put_pixels_tab[2]);
1144
                vp8_mc(s, 0, dst[2] + 4*y*s->uvlinesize + x*4,
1145
                       s->framep[mb->ref_frame]->data[2], &uvmv,
1146
                       4*x + x_off, 4*y + y_off, 4, 4,
1147
                       width, height, s->uvlinesize,
1148
                       s->put_pixels_tab[2]);
1149
            }
1150
        }
1151
        break;
1152
    }
1153
    case VP8_SPLITMVMODE_16x8:
1154
        vp8_mc_part(s, dst, s->framep[mb->ref_frame], x_off, y_off,
1155
                    0, 0, 16, 8, width, height, &mb->bmv[0]);
1156
        vp8_mc_part(s, dst, s->framep[mb->ref_frame], x_off, y_off,
1157
                    0, 8, 16, 8, width, height, &mb->bmv[1]);
1158
        break;
1159
    case VP8_SPLITMVMODE_8x16:
1160
        vp8_mc_part(s, dst, s->framep[mb->ref_frame], x_off, y_off,
1161
                    0, 0, 8, 16, width, height, &mb->bmv[0]);
1162
        vp8_mc_part(s, dst, s->framep[mb->ref_frame], x_off, y_off,
1163
                    8, 0, 8, 16, width, height, &mb->bmv[1]);
1164
        break;
1165
    case VP8_SPLITMVMODE_8x8:
1166
        vp8_mc_part(s, dst, s->framep[mb->ref_frame], x_off, y_off,
1167
                    0, 0, 8, 8, width, height, &mb->bmv[0]);
1168
        vp8_mc_part(s, dst, s->framep[mb->ref_frame], x_off, y_off,
1169
                    8, 0, 8, 8, width, height, &mb->bmv[1]);
1170
        vp8_mc_part(s, dst, s->framep[mb->ref_frame], x_off, y_off,
1171
                    0, 8, 8, 8, width, height, &mb->bmv[2]);
1172
        vp8_mc_part(s, dst, s->framep[mb->ref_frame], x_off, y_off,
1173
                    8, 8, 8, 8, width, height, &mb->bmv[3]);
1174
        break;
1175
    }
1176

    
1177
    prefetch_motion(s, mb, mb_x, mb_y, x_off, y_off, VP56_FRAME_GOLDEN);
1178
}
1179

    
1180
static void idct_mb(VP8Context *s, uint8_t *y_dst, uint8_t *u_dst, uint8_t *v_dst,
1181
                    VP8Macroblock *mb)
1182
{
1183
    int x, y, nnz;
1184

    
1185
    if (mb->mode != MODE_I4x4)
1186
        for (y = 0; y < 4; y++) {
1187
            for (x = 0; x < 4; x++) {
1188
                nnz = s->non_zero_count_cache[y][x];
1189
                if (nnz) {
1190
                    if (nnz == 1)
1191
                        s->vp8dsp.vp8_idct_dc_add(y_dst+4*x, s->block[y][x], s->linesize);
1192
                    else
1193
                        s->vp8dsp.vp8_idct_add(y_dst+4*x, s->block[y][x], s->linesize);
1194
                }
1195
            }
1196
            y_dst += 4*s->linesize;
1197
        }
1198

    
1199
    for (y = 0; y < 2; y++) {
1200
        for (x = 0; x < 2; x++) {
1201
            nnz = s->non_zero_count_cache[4][(y<<1)+x];
1202
            if (nnz) {
1203
                if (nnz == 1)
1204
                    s->vp8dsp.vp8_idct_dc_add(u_dst+4*x, s->block[4][(y<<1)+x], s->uvlinesize);
1205
                else
1206
                    s->vp8dsp.vp8_idct_add(u_dst+4*x, s->block[4][(y<<1)+x], s->uvlinesize);
1207
            }
1208

    
1209
            nnz = s->non_zero_count_cache[5][(y<<1)+x];
1210
            if (nnz) {
1211
                if (nnz == 1)
1212
                    s->vp8dsp.vp8_idct_dc_add(v_dst+4*x, s->block[5][(y<<1)+x], s->uvlinesize);
1213
                else
1214
                    s->vp8dsp.vp8_idct_add(v_dst+4*x, s->block[5][(y<<1)+x], s->uvlinesize);
1215
            }
1216
        }
1217
        u_dst += 4*s->uvlinesize;
1218
        v_dst += 4*s->uvlinesize;
1219
    }
1220
}
1221

    
1222
static void filter_level_for_mb(VP8Context *s, VP8Macroblock *mb, VP8FilterStrength *f )
1223
{
1224
    int interior_limit, filter_level;
1225

    
1226
    if (s->segmentation.enabled) {
1227
        filter_level = s->segmentation.filter_level[mb->segment];
1228
        if (!s->segmentation.absolute_vals)
1229
            filter_level += s->filter.level;
1230
    } else
1231
        filter_level = s->filter.level;
1232

    
1233
    if (s->lf_delta.enabled) {
1234
        filter_level += s->lf_delta.ref[mb->ref_frame];
1235

    
1236
        if (mb->ref_frame == VP56_FRAME_CURRENT) {
1237
            if (mb->mode == MODE_I4x4)
1238
                filter_level += s->lf_delta.mode[0];
1239
        } else {
1240
            if (mb->mode == VP8_MVMODE_ZERO)
1241
                filter_level += s->lf_delta.mode[1];
1242
            else if (mb->mode == VP8_MVMODE_SPLIT)
1243
                filter_level += s->lf_delta.mode[3];
1244
            else
1245
                filter_level += s->lf_delta.mode[2];
1246
        }
1247
    }
1248
    filter_level = av_clip(filter_level, 0, 63);
1249

    
1250
    interior_limit = filter_level;
1251
    if (s->filter.sharpness) {
1252
        interior_limit >>= s->filter.sharpness > 4 ? 2 : 1;
1253
        interior_limit = FFMIN(interior_limit, 9 - s->filter.sharpness);
1254
    }
1255
    interior_limit = FFMAX(interior_limit, 1);
1256

    
1257
    f->filter_level = filter_level;
1258
    f->inner_limit = interior_limit;
1259
}
1260

    
1261
static void filter_mb(VP8Context *s, uint8_t *dst[3], VP8Macroblock *mb, VP8FilterStrength *f, int mb_x, int mb_y)
1262
{
1263
    int mbedge_lim, bedge_lim, hev_thresh;
1264
    int filter_level = f->filter_level;
1265
    int inner_limit = f->inner_limit;
1266

    
1267
    if (!filter_level)
1268
        return;
1269

    
1270
    mbedge_lim = 2*(filter_level+2) + inner_limit;
1271
     bedge_lim = 2* filter_level    + inner_limit;
1272
    hev_thresh = filter_level >= 15;
1273

    
1274
    if (s->keyframe) {
1275
        if (filter_level >= 40)
1276
            hev_thresh = 2;
1277
    } else {
1278
        if (filter_level >= 40)
1279
            hev_thresh = 3;
1280
        else if (filter_level >= 20)
1281
            hev_thresh = 2;
1282
    }
1283

    
1284
    if (mb_x) {
1285
        s->vp8dsp.vp8_h_loop_filter16y(dst[0],     s->linesize,
1286
                                       mbedge_lim, inner_limit, hev_thresh);
1287
        s->vp8dsp.vp8_h_loop_filter8uv(dst[1],     dst[2],      s->uvlinesize,
1288
                                       mbedge_lim, inner_limit, hev_thresh);
1289
    }
1290

    
1291
    if (!mb->skip || mb->mode == MODE_I4x4 || mb->mode == VP8_MVMODE_SPLIT) {
1292
        s->vp8dsp.vp8_h_loop_filter16y_inner(dst[0]+ 4, s->linesize, bedge_lim,
1293
                                             inner_limit,   hev_thresh);
1294
        s->vp8dsp.vp8_h_loop_filter16y_inner(dst[0]+ 8, s->linesize, bedge_lim,
1295
                                             inner_limit,   hev_thresh);
1296
        s->vp8dsp.vp8_h_loop_filter16y_inner(dst[0]+12, s->linesize, bedge_lim,
1297
                                             inner_limit,   hev_thresh);
1298
        s->vp8dsp.vp8_h_loop_filter8uv_inner(dst[1] + 4,    dst[2] + 4,
1299
                                             s->uvlinesize, bedge_lim,
1300
                                             inner_limit,   hev_thresh);
1301
    }
1302

    
1303
    if (mb_y) {
1304
        s->vp8dsp.vp8_v_loop_filter16y(dst[0],     s->linesize,
1305
                                       mbedge_lim, inner_limit, hev_thresh);
1306
        s->vp8dsp.vp8_v_loop_filter8uv(dst[1],     dst[2],      s->uvlinesize,
1307
                                       mbedge_lim, inner_limit, hev_thresh);
1308
    }
1309

    
1310
    if (!mb->skip || mb->mode == MODE_I4x4 || mb->mode == VP8_MVMODE_SPLIT) {
1311
        s->vp8dsp.vp8_v_loop_filter16y_inner(dst[0]+ 4*s->linesize,
1312
                                             s->linesize,   bedge_lim,
1313
                                             inner_limit,   hev_thresh);
1314
        s->vp8dsp.vp8_v_loop_filter16y_inner(dst[0]+ 8*s->linesize,
1315
                                             s->linesize,   bedge_lim,
1316
                                             inner_limit,   hev_thresh);
1317
        s->vp8dsp.vp8_v_loop_filter16y_inner(dst[0]+12*s->linesize,
1318
                                             s->linesize,   bedge_lim,
1319
                                             inner_limit, hev_thresh);
1320
        s->vp8dsp.vp8_v_loop_filter8uv_inner(dst[1] + 4 * s->uvlinesize,
1321
                                             dst[2] + 4 * s->uvlinesize,
1322
                                             s->uvlinesize, bedge_lim,
1323
                                             inner_limit,   hev_thresh);
1324
    }
1325
}
1326

    
1327
static void filter_mb_simple(VP8Context *s, uint8_t *dst, VP8Macroblock *mb, VP8FilterStrength *f, int mb_x, int mb_y)
1328
{
1329
    int mbedge_lim, bedge_lim;
1330
    int filter_level = f->filter_level;
1331
    int inner_limit = f->inner_limit;
1332

    
1333
    if (!filter_level)
1334
        return;
1335

    
1336
    mbedge_lim = 2*(filter_level+2) + inner_limit;
1337
     bedge_lim = 2* filter_level    + inner_limit;
1338

    
1339
    if (mb_x)
1340
        s->vp8dsp.vp8_h_loop_filter_simple(dst, s->linesize, mbedge_lim);
1341
    if (!mb->skip || mb->mode == MODE_I4x4 || mb->mode == VP8_MVMODE_SPLIT) {
1342
        s->vp8dsp.vp8_h_loop_filter_simple(dst+ 4, s->linesize, bedge_lim);
1343
        s->vp8dsp.vp8_h_loop_filter_simple(dst+ 8, s->linesize, bedge_lim);
1344
        s->vp8dsp.vp8_h_loop_filter_simple(dst+12, s->linesize, bedge_lim);
1345
    }
1346

    
1347
    if (mb_y)
1348
        s->vp8dsp.vp8_v_loop_filter_simple(dst, s->linesize, mbedge_lim);
1349
    if (!mb->skip || mb->mode == MODE_I4x4 || mb->mode == VP8_MVMODE_SPLIT) {
1350
        s->vp8dsp.vp8_v_loop_filter_simple(dst+ 4*s->linesize, s->linesize, bedge_lim);
1351
        s->vp8dsp.vp8_v_loop_filter_simple(dst+ 8*s->linesize, s->linesize, bedge_lim);
1352
        s->vp8dsp.vp8_v_loop_filter_simple(dst+12*s->linesize, s->linesize, bedge_lim);
1353
    }
1354
}
1355

    
1356
static void filter_mb_row(VP8Context *s, int mb_y)
1357
{
1358
    VP8FilterStrength *f = s->filter_strength;
1359
    VP8Macroblock *mb = s->macroblocks + mb_y*s->mb_stride;
1360
    uint8_t *dst[3] = {
1361
        s->framep[VP56_FRAME_CURRENT]->data[0] + 16*mb_y*s->linesize,
1362
        s->framep[VP56_FRAME_CURRENT]->data[1] +  8*mb_y*s->uvlinesize,
1363
        s->framep[VP56_FRAME_CURRENT]->data[2] +  8*mb_y*s->uvlinesize
1364
    };
1365
    int mb_x;
1366

    
1367
    for (mb_x = 0; mb_x < s->mb_width; mb_x++) {
1368
        backup_mb_border(s->top_border[mb_x+1], dst[0], dst[1], dst[2], s->linesize, s->uvlinesize, 0);
1369
        filter_mb(s, dst, mb++, f++, mb_x, mb_y);
1370
        dst[0] += 16;
1371
        dst[1] += 8;
1372
        dst[2] += 8;
1373
    }
1374
}
1375

    
1376
static void filter_mb_row_simple(VP8Context *s, int mb_y)
1377
{
1378
    VP8FilterStrength *f = s->filter_strength;
1379
    VP8Macroblock *mb = s->macroblocks + mb_y*s->mb_stride;
1380
    uint8_t *dst = s->framep[VP56_FRAME_CURRENT]->data[0] + 16*mb_y*s->linesize;
1381
    int mb_x;
1382

    
1383
    for (mb_x = 0; mb_x < s->mb_width; mb_x++) {
1384
        backup_mb_border(s->top_border[mb_x+1], dst, NULL, NULL, s->linesize, 0, 1);
1385
        filter_mb_simple(s, dst, mb++, f++, mb_x, mb_y);
1386
        dst += 16;
1387
    }
1388
}
1389

    
1390
static int vp8_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
1391
                            AVPacket *avpkt)
1392
{
1393
    VP8Context *s = avctx->priv_data;
1394
    int ret, mb_x, mb_y, i, y, referenced;
1395
    enum AVDiscard skip_thresh;
1396
    AVFrame *curframe;
1397

    
1398
    if ((ret = decode_frame_header(s, avpkt->data, avpkt->size)) < 0)
1399
        return ret;
1400

    
1401
    referenced = s->update_last || s->update_golden == VP56_FRAME_CURRENT
1402
                                || s->update_altref == VP56_FRAME_CURRENT;
1403

    
1404
    skip_thresh = !referenced ? AVDISCARD_NONREF :
1405
                    !s->keyframe ? AVDISCARD_NONKEY : AVDISCARD_ALL;
1406

    
1407
    if (avctx->skip_frame >= skip_thresh) {
1408
        s->invisible = 1;
1409
        goto skip_decode;
1410
    }
1411
    s->deblock_filter = s->filter.level && avctx->skip_loop_filter < skip_thresh;
1412

    
1413
    for (i = 0; i < 4; i++)
1414
        if (&s->frames[i] != s->framep[VP56_FRAME_PREVIOUS] &&
1415
            &s->frames[i] != s->framep[VP56_FRAME_GOLDEN] &&
1416
            &s->frames[i] != s->framep[VP56_FRAME_GOLDEN2]) {
1417
            curframe = s->framep[VP56_FRAME_CURRENT] = &s->frames[i];
1418
            break;
1419
        }
1420
    if (curframe->data[0])
1421
        avctx->release_buffer(avctx, curframe);
1422

    
1423
    curframe->key_frame = s->keyframe;
1424
    curframe->pict_type = s->keyframe ? FF_I_TYPE : FF_P_TYPE;
1425
    curframe->reference = referenced ? 3 : 0;
1426
    if ((ret = avctx->get_buffer(avctx, curframe))) {
1427
        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed!\n");
1428
        return ret;
1429
    }
1430

    
1431
    // Given that arithmetic probabilities are updated every frame, it's quite likely
1432
    // that the values we have on a random interframe are complete junk if we didn't
1433
    // start decode on a keyframe. So just don't display anything rather than junk.
1434
    if (!s->keyframe && (!s->framep[VP56_FRAME_PREVIOUS] ||
1435
                         !s->framep[VP56_FRAME_GOLDEN] ||
1436
                         !s->framep[VP56_FRAME_GOLDEN2])) {
1437
        av_log(avctx, AV_LOG_WARNING, "Discarding interframe without a prior keyframe!\n");
1438
        return AVERROR_INVALIDDATA;
1439
    }
1440

    
1441
    s->linesize   = curframe->linesize[0];
1442
    s->uvlinesize = curframe->linesize[1];
1443

    
1444
    if (!s->edge_emu_buffer)
1445
        s->edge_emu_buffer = av_malloc(21*s->linesize);
1446

    
1447
    memset(s->top_nnz, 0, s->mb_width*sizeof(*s->top_nnz));
1448

    
1449
    // top edge of 127 for intra prediction
1450
    memset(s->top_border, 127, (s->mb_width+1)*sizeof(*s->top_border));
1451

    
1452
    for (mb_y = 0; mb_y < s->mb_height; mb_y++) {
1453
        VP56RangeCoder *c = &s->coeff_partition[mb_y & (s->num_coeff_partitions-1)];
1454
        VP8Macroblock *mb = s->macroblocks + mb_y*s->mb_stride;
1455
        uint8_t *intra4x4 = s->intra4x4_pred_mode + 4*mb_y*s->b4_stride;
1456
        uint8_t *dst[3] = {
1457
            curframe->data[0] + 16*mb_y*s->linesize,
1458
            curframe->data[1] +  8*mb_y*s->uvlinesize,
1459
            curframe->data[2] +  8*mb_y*s->uvlinesize
1460
        };
1461

    
1462
        memset(s->left_nnz, 0, sizeof(s->left_nnz));
1463

    
1464
        // left edge of 129 for intra prediction
1465
        if (!(avctx->flags & CODEC_FLAG_EMU_EDGE))
1466
            for (i = 0; i < 3; i++)
1467
                for (y = 0; y < 16>>!!i; y++)
1468
                    dst[i][y*curframe->linesize[i]-1] = 129;
1469
        if (mb_y)
1470
            memset(s->top_border, 129, sizeof(*s->top_border));
1471

    
1472
        for (mb_x = 0; mb_x < s->mb_width; mb_x++) {
1473
            uint8_t *intra4x4_mb = s->keyframe ? intra4x4 + 4*mb_x : s->intra4x4_pred_mode_mb;
1474

    
1475
            /* Prefetch the current frame, 4 MBs ahead */
1476
            s->dsp.prefetch(dst[0] + (mb_x&3)*4*s->linesize + 64, s->linesize, 4);
1477
            s->dsp.prefetch(dst[1] + (mb_x&7)*s->uvlinesize + 64, dst[2] - dst[1], 2);
1478

    
1479
            decode_mb_mode(s, mb, mb_x, mb_y, intra4x4_mb);
1480

    
1481
            if (!mb->skip)
1482
                decode_mb_coeffs(s, c, mb, s->top_nnz[mb_x], s->left_nnz);
1483
            else {
1484
                AV_ZERO128(s->non_zero_count_cache);    // luma
1485
                AV_ZERO64(s->non_zero_count_cache[4]);  // chroma
1486
            }
1487

    
1488
            if (mb->mode <= MODE_I4x4) {
1489
                intra_predict(s, dst, mb, intra4x4_mb, mb_x, mb_y);
1490
                memset(mb->bmv, 0, sizeof(mb->bmv));
1491
            } else {
1492
                inter_predict(s, dst, mb, mb_x, mb_y);
1493
            }
1494

    
1495
            if (!mb->skip) {
1496
                idct_mb(s, dst[0], dst[1], dst[2], mb);
1497
            } else {
1498
                AV_ZERO64(s->left_nnz);
1499
                AV_WN64(s->top_nnz[mb_x], 0);   // array of 9, so unaligned
1500

    
1501
                // Reset DC block predictors if they would exist if the mb had coefficients
1502
                if (mb->mode != MODE_I4x4 && mb->mode != VP8_MVMODE_SPLIT) {
1503
                    s->left_nnz[8]      = 0;
1504
                    s->top_nnz[mb_x][8] = 0;
1505
                }
1506
            }
1507

    
1508
            if (s->deblock_filter)
1509
                filter_level_for_mb(s, mb, &s->filter_strength[mb_x]);
1510

    
1511
            dst[0] += 16;
1512
            dst[1] += 8;
1513
            dst[2] += 8;
1514
            mb++;
1515
        }
1516
        if (s->deblock_filter) {
1517
            if (s->filter.simple)
1518
                filter_mb_row_simple(s, mb_y);
1519
            else
1520
                filter_mb_row(s, mb_y);
1521
        }
1522
    }
1523

    
1524
skip_decode:
1525
    // if future frames don't use the updated probabilities,
1526
    // reset them to the values we saved
1527
    if (!s->update_probabilities)
1528
        s->prob[0] = s->prob[1];
1529

    
1530
    // check if golden and altref are swapped
1531
    if (s->update_altref == VP56_FRAME_GOLDEN &&
1532
        s->update_golden == VP56_FRAME_GOLDEN2)
1533
        FFSWAP(AVFrame *, s->framep[VP56_FRAME_GOLDEN], s->framep[VP56_FRAME_GOLDEN2]);
1534
    else {
1535
        if (s->update_altref != VP56_FRAME_NONE)
1536
            s->framep[VP56_FRAME_GOLDEN2] = s->framep[s->update_altref];
1537

    
1538
        if (s->update_golden != VP56_FRAME_NONE)
1539
            s->framep[VP56_FRAME_GOLDEN] = s->framep[s->update_golden];
1540
    }
1541

    
1542
    if (s->update_last) // move cur->prev
1543
        s->framep[VP56_FRAME_PREVIOUS] = s->framep[VP56_FRAME_CURRENT];
1544

    
1545
    // release no longer referenced frames
1546
    for (i = 0; i < 4; i++)
1547
        if (s->frames[i].data[0] &&
1548
            &s->frames[i] != s->framep[VP56_FRAME_CURRENT] &&
1549
            &s->frames[i] != s->framep[VP56_FRAME_PREVIOUS] &&
1550
            &s->frames[i] != s->framep[VP56_FRAME_GOLDEN] &&
1551
            &s->frames[i] != s->framep[VP56_FRAME_GOLDEN2])
1552
            avctx->release_buffer(avctx, &s->frames[i]);
1553

    
1554
    if (!s->invisible) {
1555
        *(AVFrame*)data = *s->framep[VP56_FRAME_CURRENT];
1556
        *data_size = sizeof(AVFrame);
1557
    }
1558

    
1559
    return avpkt->size;
1560
}
1561

    
1562
static av_cold int vp8_decode_init(AVCodecContext *avctx)
1563
{
1564
    VP8Context *s = avctx->priv_data;
1565

    
1566
    s->avctx = avctx;
1567
    avctx->pix_fmt = PIX_FMT_YUV420P;
1568

    
1569
    dsputil_init(&s->dsp, avctx);
1570
    ff_h264_pred_init(&s->hpc, CODEC_ID_VP8);
1571
    ff_vp8dsp_init(&s->vp8dsp);
1572

    
1573
    // intra pred needs edge emulation among other things
1574
    if (avctx->flags&CODEC_FLAG_EMU_EDGE) {
1575
        av_log(avctx, AV_LOG_ERROR, "Edge emulation not supported\n");
1576
        return AVERROR_PATCHWELCOME;
1577
    }
1578

    
1579
    return 0;
1580
}
1581

    
1582
static av_cold int vp8_decode_free(AVCodecContext *avctx)
1583
{
1584
    vp8_decode_flush(avctx);
1585
    return 0;
1586
}
1587

    
1588
AVCodec vp8_decoder = {
1589
    "vp8",
1590
    AVMEDIA_TYPE_VIDEO,
1591
    CODEC_ID_VP8,
1592
    sizeof(VP8Context),
1593
    vp8_decode_init,
1594
    NULL,
1595
    vp8_decode_free,
1596
    vp8_decode_frame,
1597
    CODEC_CAP_DR1,
1598
    .flush = vp8_decode_flush,
1599
    .long_name = NULL_IF_CONFIG_SMALL("On2 VP8"),
1600
};