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ffmpeg / libavcodec / motionpixels.c @ 72415b2a

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/*
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 * Motion Pixels Video Decoder
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 * Copyright (c) 2008 Gregory Montoir (cyx@users.sourceforge.net)
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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 "get_bits.h"
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#include "dsputil.h"
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#define MAX_HUFF_CODES 16
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#include "motionpixels_tablegen.h"
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typedef struct HuffCode {
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    int code;
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    uint8_t size;
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    uint8_t delta;
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} HuffCode;
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typedef struct MotionPixelsContext {
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    AVCodecContext *avctx;
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    AVFrame frame;
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    DSPContext dsp;
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    uint8_t *changes_map;
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    int offset_bits_len;
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    int codes_count, current_codes_count;
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    int max_codes_bits;
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    HuffCode codes[MAX_HUFF_CODES];
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    VLC vlc;
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    YuvPixel *vpt, *hpt;
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    uint8_t gradient_scale[3];
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    uint8_t *bswapbuf;
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    int bswapbuf_size;
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} MotionPixelsContext;
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static av_cold int mp_decode_init(AVCodecContext *avctx)
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{
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    MotionPixelsContext *mp = avctx->priv_data;
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    motionpixels_tableinit();
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    mp->avctx = avctx;
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    dsputil_init(&mp->dsp, avctx);
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    mp->changes_map = av_mallocz(avctx->width * avctx->height);
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    mp->offset_bits_len = av_log2(avctx->width * avctx->height) + 1;
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    mp->vpt = av_mallocz(avctx->height * sizeof(YuvPixel));
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    mp->hpt = av_mallocz(avctx->height * avctx->width / 16 * sizeof(YuvPixel));
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    avctx->pix_fmt = PIX_FMT_RGB555;
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    return 0;
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}
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static void mp_read_changes_map(MotionPixelsContext *mp, GetBitContext *gb, int count, int bits_len, int read_color)
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{
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    uint16_t *pixels;
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    int offset, w, h, color = 0, x, y, i;
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    while (count--) {
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        offset = get_bits_long(gb, mp->offset_bits_len);
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        w      = get_bits(gb, bits_len) + 1;
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        h      = get_bits(gb, bits_len) + 1;
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        if (read_color)
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            color = get_bits(gb, 15);
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        x = offset % mp->avctx->width;
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        y = offset / mp->avctx->width;
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        if (y >= mp->avctx->height)
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            continue;
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        w = FFMIN(w, mp->avctx->width  - x);
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        h = FFMIN(h, mp->avctx->height - y);
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        pixels = (uint16_t *)&mp->frame.data[0][y * mp->frame.linesize[0] + x * 2];
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        while (h--) {
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            mp->changes_map[offset] = w;
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            if (read_color)
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                for (i = 0; i < w; ++i)
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                    pixels[i] = color;
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            offset += mp->avctx->width;
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            pixels += mp->frame.linesize[0] / 2;
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        }
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    }
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}
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static void mp_get_code(MotionPixelsContext *mp, GetBitContext *gb, int size, int code)
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{
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    while (get_bits1(gb)) {
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        ++size;
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        if (size > mp->max_codes_bits) {
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            av_log(mp->avctx, AV_LOG_ERROR, "invalid code size %d/%d\n", size, mp->max_codes_bits);
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            return;
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        }
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        code <<= 1;
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        mp_get_code(mp, gb, size, code + 1);
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    }
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    if (mp->current_codes_count >= MAX_HUFF_CODES) {
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        av_log(mp->avctx, AV_LOG_ERROR, "too many codes\n");
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        return;
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    }
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    mp->codes[mp->current_codes_count  ].code = code;
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    mp->codes[mp->current_codes_count++].size = size;
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}
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static void mp_read_codes_table(MotionPixelsContext *mp, GetBitContext *gb)
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{
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    if (mp->codes_count == 1) {
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        mp->codes[0].delta = get_bits(gb, 4);
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    } else {
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        int i;
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        mp->max_codes_bits = get_bits(gb, 4);
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        for (i = 0; i < mp->codes_count; ++i)
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            mp->codes[i].delta = get_bits(gb, 4);
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        mp->current_codes_count = 0;
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        mp_get_code(mp, gb, 0, 0);
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   }
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}
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static int mp_gradient(MotionPixelsContext *mp, int component, int v)
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{
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    int delta;
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    delta = (v - 7) * mp->gradient_scale[component];
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    mp->gradient_scale[component] = (v == 0 || v == 14) ? 2 : 1;
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    return delta;
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}
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static YuvPixel mp_get_yuv_from_rgb(MotionPixelsContext *mp, int x, int y)
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{
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    int color;
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    color = *(uint16_t *)&mp->frame.data[0][y * mp->frame.linesize[0] + x * 2];
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    return mp_rgb_yuv_table[color];
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}
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static void mp_set_rgb_from_yuv(MotionPixelsContext *mp, int x, int y, const YuvPixel *p)
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{
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    int color;
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    color = mp_yuv_to_rgb(p->y, p->v, p->u, 1);
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    *(uint16_t *)&mp->frame.data[0][y * mp->frame.linesize[0] + x * 2] = color;
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}
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static int mp_get_vlc(MotionPixelsContext *mp, GetBitContext *gb)
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{
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    int i;
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    i = (mp->codes_count == 1) ? 0 : get_vlc2(gb, mp->vlc.table, mp->max_codes_bits, 1);
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    return mp->codes[i].delta;
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}
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static void mp_decode_line(MotionPixelsContext *mp, GetBitContext *gb, int y)
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{
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    YuvPixel p;
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    const int y0 = y * mp->avctx->width;
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    int w, i, x = 0;
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    p = mp->vpt[y];
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    if (mp->changes_map[y0 + x] == 0) {
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        memset(mp->gradient_scale, 1, sizeof(mp->gradient_scale));
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        ++x;
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    }
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    while (x < mp->avctx->width) {
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        w = mp->changes_map[y0 + x];
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        if (w != 0) {
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            if ((y & 3) == 0) {
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                if (mp->changes_map[y0 + x + mp->avctx->width] < w ||
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                    mp->changes_map[y0 + x + mp->avctx->width * 2] < w ||
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                    mp->changes_map[y0 + x + mp->avctx->width * 3] < w) {
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                    for (i = (x + 3) & ~3; i < x + w; i += 4) {
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                        mp->hpt[((y / 4) * mp->avctx->width + i) / 4] = mp_get_yuv_from_rgb(mp, i, y);
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                    }
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                }
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            }
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            x += w;
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            memset(mp->gradient_scale, 1, sizeof(mp->gradient_scale));
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            p = mp_get_yuv_from_rgb(mp, x - 1, y);
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        } else {
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            p.y += mp_gradient(mp, 0, mp_get_vlc(mp, gb));
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            if ((x & 3) == 0) {
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                if ((y & 3) == 0) {
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                    p.v += mp_gradient(mp, 1, mp_get_vlc(mp, gb));
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                    p.u += mp_gradient(mp, 2, mp_get_vlc(mp, gb));
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                    mp->hpt[((y / 4) * mp->avctx->width + x) / 4] = p;
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                } else {
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                    p.v = mp->hpt[((y / 4) * mp->avctx->width + x) / 4].v;
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                    p.u = mp->hpt[((y / 4) * mp->avctx->width + x) / 4].u;
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                }
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            }
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            mp_set_rgb_from_yuv(mp, x, y, &p);
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            ++x;
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        }
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    }
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}
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static void mp_decode_frame_helper(MotionPixelsContext *mp, GetBitContext *gb)
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{
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    YuvPixel p;
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    int y, y0;
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    for (y = 0; y < mp->avctx->height; ++y) {
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        if (mp->changes_map[y * mp->avctx->width] != 0) {
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            memset(mp->gradient_scale, 1, sizeof(mp->gradient_scale));
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            p = mp_get_yuv_from_rgb(mp, 0, y);
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        } else {
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            p.y += mp_gradient(mp, 0, mp_get_vlc(mp, gb));
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            if ((y & 3) == 0) {
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                p.v += mp_gradient(mp, 1, mp_get_vlc(mp, gb));
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                p.u += mp_gradient(mp, 2, mp_get_vlc(mp, gb));
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            }
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            mp->vpt[y] = p;
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            mp_set_rgb_from_yuv(mp, 0, y, &p);
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        }
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    }
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    for (y0 = 0; y0 < 2; ++y0)
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        for (y = y0; y < mp->avctx->height; y += 2)
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            mp_decode_line(mp, gb, y);
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}
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static int mp_decode_frame(AVCodecContext *avctx,
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                                 void *data, int *data_size,
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                                 AVPacket *avpkt)
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{
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    const uint8_t *buf = avpkt->data;
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    int buf_size = avpkt->size;
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    MotionPixelsContext *mp = avctx->priv_data;
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    GetBitContext gb;
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    int i, count1, count2, sz;
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    mp->frame.reference = 1;
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    mp->frame.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE;
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    if (avctx->reget_buffer(avctx, &mp->frame)) {
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        av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
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        return -1;
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    }
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    /* le32 bitstream msb first */
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    av_fast_malloc(&mp->bswapbuf, &mp->bswapbuf_size, buf_size + FF_INPUT_BUFFER_PADDING_SIZE);
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    if (!mp->bswapbuf)
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        return AVERROR(ENOMEM);
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    mp->dsp.bswap_buf((uint32_t *)mp->bswapbuf, (const uint32_t *)buf, buf_size / 4);
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    if (buf_size & 3)
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        memcpy(mp->bswapbuf + (buf_size & ~3), buf + (buf_size & ~3), buf_size & 3);
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    init_get_bits(&gb, mp->bswapbuf, buf_size * 8);
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    memset(mp->changes_map, 0, avctx->width * avctx->height);
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    for (i = !(avctx->extradata[1] & 2); i < 2; ++i) {
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        count1 = get_bits(&gb, 12);
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        count2 = get_bits(&gb, 12);
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        mp_read_changes_map(mp, &gb, count1, 8, i);
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        mp_read_changes_map(mp, &gb, count2, 4, i);
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    }
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    mp->codes_count = get_bits(&gb, 4);
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    if (mp->codes_count == 0)
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        goto end;
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    if (mp->changes_map[0] == 0) {
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        *(uint16_t *)mp->frame.data[0] = get_bits(&gb, 15);
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        mp->changes_map[0] = 1;
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    }
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    mp_read_codes_table(mp, &gb);
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    sz = get_bits(&gb, 18);
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    if (avctx->extradata[0] != 5)
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        sz += get_bits(&gb, 18);
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    if (sz == 0)
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        goto end;
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    init_vlc(&mp->vlc, mp->max_codes_bits, mp->codes_count, &mp->codes[0].size, sizeof(HuffCode), 1, &mp->codes[0].code, sizeof(HuffCode), 4, 0);
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    mp_decode_frame_helper(mp, &gb);
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    free_vlc(&mp->vlc);
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end:
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    *data_size = sizeof(AVFrame);
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    *(AVFrame *)data = mp->frame;
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    return buf_size;
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}
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static av_cold int mp_decode_end(AVCodecContext *avctx)
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{
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    MotionPixelsContext *mp = avctx->priv_data;
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    av_freep(&mp->changes_map);
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    av_freep(&mp->vpt);
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    av_freep(&mp->hpt);
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    av_freep(&mp->bswapbuf);
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    if (mp->frame.data[0])
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        avctx->release_buffer(avctx, &mp->frame);
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    return 0;
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}
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AVCodec motionpixels_decoder = {
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    "motionpixels",
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    AVMEDIA_TYPE_VIDEO,
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    CODEC_ID_MOTIONPIXELS,
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    sizeof(MotionPixelsContext),
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    mp_decode_init,
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    NULL,
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    mp_decode_end,
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    mp_decode_frame,
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    CODEC_CAP_DR1,
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    .long_name = NULL_IF_CONFIG_SMALL("Motion Pixels video"),
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};