PeerStreamer

/**

 * VP8 compatible video decoder

 *

 * Copyright (C) 2010 David Conrad

 * Copyright (C) 2010 Ronald S. Bultje

 * Copyright (C) 2010 Jason Garrett-Glaser

 *

 * This file is part of FFmpeg.

 *

 * FFmpeg is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * FFmpeg is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with FFmpeg; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

 */

#ifndef AVCODEC_VP8_H

#define AVCODEC_VP8_H

#include "vp56.h"

#include "vp56data.h"

#include "vp8dsp.h"

#include "h264pred.h"

#define VP8_MAX_QUANT 127

enum dct_token {

    DCT_0,

    DCT_1,

    DCT_2,

    DCT_3,

    DCT_4,

    DCT_CAT1,

    DCT_CAT2,

    DCT_CAT3,

    DCT_CAT4,

    DCT_CAT5,

    DCT_CAT6,

    DCT_EOB,

    NUM_DCT_TOKENS

};

// used to signal 4x4 intra pred in luma MBs

#define MODE_I4x4 4

enum inter_mvmode {

    VP8_MVMODE_ZERO = MODE_I4x4 + 1,

    VP8_MVMODE_MV,

    VP8_MVMODE_SPLIT

};

enum inter_splitmvmode {

    VP8_SPLITMVMODE_16x8 = 0,    ///< 2 16x8 blocks (vertical)

    VP8_SPLITMVMODE_8x16,        ///< 2 8x16 blocks (horizontal)

    VP8_SPLITMVMODE_8x8,         ///< 2x2 blocks of 8x8px each

    VP8_SPLITMVMODE_4x4,         ///< 4x4 blocks of 4x4px each

    VP8_SPLITMVMODE_NONE,        ///< (only used in prediction) no split MVs

};

typedef struct {

    uint8_t filter_level;

    uint8_t inner_limit;

    uint8_t inner_filter;

} VP8FilterStrength;

typedef struct {

    uint8_t skip;

    // todo: make it possible to check for at least (i4x4 or split_mv)

    // in one op. are others needed?

    uint8_t mode;

    uint8_t ref_frame;

    uint8_t partitioning;

    VP56mv mv;

    VP56mv bmv[16];

} VP8Macroblock;

typedef struct {

    AVCodecContext *avctx;

    DSPContext dsp;

    VP8DSPContext vp8dsp;

    H264PredContext hpc;

    vp8_mc_func put_pixels_tab[3][3][3];

    AVFrame frames[4];

    AVFrame *framep[4];

    uint8_t *edge_emu_buffer;

    VP56RangeCoder c;   ///< header context, includes mb modes and motion vectors

    int profile;

    int mb_width;   /* number of horizontal MB */

    int mb_height;  /* number of vertical MB */

    int linesize;

    int uvlinesize;

    int keyframe;

    int invisible;

    int update_last;    ///< update VP56_FRAME_PREVIOUS with the current one

    int update_golden;  ///< VP56_FRAME_NONE if not updated, or which frame to copy if so

    int update_altref;

    int deblock_filter;

    /**

     * If this flag is not set, all the probability updates

     * are discarded after this frame is decoded.

     */

    int update_probabilities;

    /**

     * All coefficients are contained in separate arith coding contexts.

     * There can be 1, 2, 4, or 8 of these after the header context.

     */

    int num_coeff_partitions;

    VP56RangeCoder coeff_partition[8];

    VP8Macroblock *macroblocks;

    VP8Macroblock *macroblocks_base;

    VP8FilterStrength *filter_strength;

    uint8_t *intra4x4_pred_mode_top;

    uint8_t intra4x4_pred_mode_left[4];

    uint8_t *segmentation_map;

    /**

     * Cache of the top row needed for intra prediction

     * 16 for luma, 8 for each chroma plane

     */

    uint8_t (*top_border)[16+8+8];

    /**

     * For coeff decode, we need to know whether the above block had non-zero

     * coefficients. This means for each macroblock, we need data for 4 luma

     * blocks, 2 u blocks, 2 v blocks, and the luma dc block, for a total of 9

     * per macroblock. We keep the last row in top_nnz.

     */

    uint8_t (*top_nnz)[9];

    DECLARE_ALIGNED(8, uint8_t, left_nnz)[9];

    /**

     * This is the index plus one of the last non-zero coeff

     * for each of the blocks in the current macroblock.

     * So, 0 -> no coeffs

     *     1 -> dc-only (special transform)

     *     2+-> full transform

     */

    DECLARE_ALIGNED(16, uint8_t, non_zero_count_cache)[6][4];

    DECLARE_ALIGNED(16, DCTELEM, block)[6][4][16];

    DECLARE_ALIGNED(16, DCTELEM, block_dc)[16];

    uint8_t intra4x4_pred_mode_mb[16];

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

    int segment;             ///< segment of the current macroblock

    VP56mv mv_min;

    VP56mv mv_max;

    int mbskip_enabled;

    int sign_bias[4]; ///< one state [0, 1] per ref frame type

    int ref_count[3];

    /**

     * Base parameters for segmentation, i.e. per-macroblock parameters.

     * These must be kept unchanged even if segmentation is not used for

     * a frame, since the values persist between interframes.

     */

    struct {

        int enabled;

        int absolute_vals;

        int update_map;

        int8_t base_quant[4];

        int8_t filter_level[4];     ///< base loop filter level

    } segmentation;

    /**

     * Macroblocks can have one of 4 different quants in a frame when

     * segmentation is enabled.

     * If segmentation is disabled, only the first segment's values are used.

     */

    struct {

        // [0] - DC qmul  [1] - AC qmul

        int16_t luma_qmul[2];

        int16_t luma_dc_qmul[2];    ///< luma dc-only block quant

        int16_t chroma_qmul[2];

    } qmat[4];

    struct {

        int simple;

        int level;

        int sharpness;

    } filter;

    struct {

        int enabled;    ///< whether each mb can have a different strength based on mode/ref

        /**

         * filter strength adjustment for the following macroblock modes:

         * [0-3] - i16x16 (always zero)

         * [4]   - i4x4

         * [5]   - zero mv

         * [6]   - inter modes except for zero or split mv

         * [7]   - split mv

         *  i16x16 modes never have any adjustment

         */

        int8_t mode[VP8_MVMODE_SPLIT+1];

        /**

         * filter strength adjustment for macroblocks that reference:

         * [0] - intra / VP56_FRAME_CURRENT

         * [1] - VP56_FRAME_PREVIOUS

         * [2] - VP56_FRAME_GOLDEN

         * [3] - altref / VP56_FRAME_GOLDEN2

         */

        int8_t ref[4];

    } lf_delta;

    /**

     * These are all of the updatable probabilities for binary decisions.

     * They are only implictly reset on keyframes, making it quite likely

     * for an interframe to desync if a prior frame's header was corrupt

     * or missing outright!

     */

    struct {

        uint8_t segmentid[3];

        uint8_t mbskip;

        uint8_t intra;

        uint8_t last;

        uint8_t golden;

        uint8_t pred16x16[4];

        uint8_t pred8x8c[3];

        /* Padded to allow overreads */

        uint8_t token[4][17][3][NUM_DCT_TOKENS-1];

        uint8_t mvc[2][19];

    } prob[2];

} VP8Context;

#endif