Subversion Repositories Kolibri OS

Rev

Go to most recent revision | Blame | Last modification | View Log | RSS feed

  1. /*
  2.  * Creative YUV (CYUV) Video Decoder
  3.  *   by Mike Melanson (melanson@pcisys.net)
  4.  * based on "Creative YUV (CYUV) stream format for AVI":
  5.  *   http://www.csse.monash.edu.au/~timf/videocodec/cyuv.txt
  6.  *
  7.  * Copyright (C) 2003 the ffmpeg project
  8.  *
  9.  * This file is part of FFmpeg.
  10.  *
  11.  * FFmpeg is free software; you can redistribute it and/or
  12.  * modify it under the terms of the GNU Lesser General Public
  13.  * License as published by the Free Software Foundation; either
  14.  * version 2.1 of the License, or (at your option) any later version.
  15.  *
  16.  * FFmpeg is distributed in the hope that it will be useful,
  17.  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18.  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  19.  * Lesser General Public License for more details.
  20.  *
  21.  * You should have received a copy of the GNU Lesser General Public
  22.  * License along with FFmpeg; if not, write to the Free Software
  23.  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  24.  */
  25.  
  26. /**
  27.  * @file
  28.  * Creative YUV (CYUV) Video Decoder.
  29.  */
  30.  
  31. #include <stdio.h>
  32. #include <stdlib.h>
  33. #include <string.h>
  34.  
  35. #include "avcodec.h"
  36. #include "internal.h"
  37. #include "libavutil/internal.h"
  38.  
  39.  
  40. typedef struct CyuvDecodeContext {
  41.     AVCodecContext *avctx;
  42.     int width, height;
  43. } CyuvDecodeContext;
  44.  
  45. static av_cold int cyuv_decode_init(AVCodecContext *avctx)
  46. {
  47.     CyuvDecodeContext *s = avctx->priv_data;
  48.  
  49.     s->avctx = avctx;
  50.     s->width = avctx->width;
  51.     /* width needs to be divisible by 4 for this codec to work */
  52.     if (s->width & 0x3)
  53.         return AVERROR_INVALIDDATA;
  54.     s->height = avctx->height;
  55.  
  56.     return 0;
  57. }
  58.  
  59. static int cyuv_decode_frame(AVCodecContext *avctx,
  60.                              void *data, int *got_frame,
  61.                              AVPacket *avpkt)
  62. {
  63.     const uint8_t *buf = avpkt->data;
  64.     int buf_size = avpkt->size;
  65.     CyuvDecodeContext *s=avctx->priv_data;
  66.     AVFrame *frame = data;
  67.  
  68.     unsigned char *y_plane;
  69.     unsigned char *u_plane;
  70.     unsigned char *v_plane;
  71.     int y_ptr;
  72.     int u_ptr;
  73.     int v_ptr;
  74.  
  75.     /* prediction error tables (make it clear that they are signed values) */
  76.     const signed char *y_table = (const signed char*)buf +  0;
  77.     const signed char *u_table = (const signed char*)buf + 16;
  78.     const signed char *v_table = (const signed char*)buf + 32;
  79.  
  80.     unsigned char y_pred, u_pred, v_pred;
  81.     int stream_ptr;
  82.     unsigned char cur_byte;
  83.     int pixel_groups;
  84.     int rawsize = s->height * FFALIGN(s->width,2) * 2;
  85.     int ret;
  86.  
  87.     if (avctx->codec_id == AV_CODEC_ID_AURA) {
  88.         y_table = u_table;
  89.         u_table = v_table;
  90.     }
  91.     /* sanity check the buffer size: A buffer has 3x16-bytes tables
  92.      * followed by (height) lines each with 3 bytes to represent groups
  93.      * of 4 pixels. Thus, the total size of the buffer ought to be:
  94.      *    (3 * 16) + height * (width * 3 / 4) */
  95.     if (buf_size == 48 + s->height * (s->width * 3 / 4)) {
  96.         avctx->pix_fmt = AV_PIX_FMT_YUV411P;
  97.     } else if(buf_size == rawsize ) {
  98.         avctx->pix_fmt = AV_PIX_FMT_UYVY422;
  99.     } else {
  100.         av_log(avctx, AV_LOG_ERROR, "got a buffer with %d bytes when %d were expected\n",
  101.                buf_size, 48 + s->height * (s->width * 3 / 4));
  102.         return AVERROR_INVALIDDATA;
  103.     }
  104.  
  105.     /* pixel data starts 48 bytes in, after 3x16-byte tables */
  106.     stream_ptr = 48;
  107.  
  108.     if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
  109.         return ret;
  110.  
  111.     y_plane = frame->data[0];
  112.     u_plane = frame->data[1];
  113.     v_plane = frame->data[2];
  114.  
  115.     if (buf_size == rawsize) {
  116.         int linesize = FFALIGN(s->width,2) * 2;
  117.         y_plane += frame->linesize[0] * s->height;
  118.         for (stream_ptr = 0; stream_ptr < rawsize; stream_ptr += linesize) {
  119.             y_plane -= frame->linesize[0];
  120.             memcpy(y_plane, buf+stream_ptr, linesize);
  121.         }
  122.     } else {
  123.  
  124.     /* iterate through each line in the height */
  125.     for (y_ptr = 0, u_ptr = 0, v_ptr = 0;
  126.          y_ptr < (s->height * frame->linesize[0]);
  127.          y_ptr += frame->linesize[0] - s->width,
  128.          u_ptr += frame->linesize[1] - s->width / 4,
  129.          v_ptr += frame->linesize[2] - s->width / 4) {
  130.  
  131.         /* reset predictors */
  132.         cur_byte = buf[stream_ptr++];
  133.         u_plane[u_ptr++] = u_pred = cur_byte & 0xF0;
  134.         y_plane[y_ptr++] = y_pred = (cur_byte & 0x0F) << 4;
  135.  
  136.         cur_byte = buf[stream_ptr++];
  137.         v_plane[v_ptr++] = v_pred = cur_byte & 0xF0;
  138.         y_pred += y_table[cur_byte & 0x0F];
  139.         y_plane[y_ptr++] = y_pred;
  140.  
  141.         cur_byte = buf[stream_ptr++];
  142.         y_pred += y_table[cur_byte & 0x0F];
  143.         y_plane[y_ptr++] = y_pred;
  144.         y_pred += y_table[(cur_byte & 0xF0) >> 4];
  145.         y_plane[y_ptr++] = y_pred;
  146.  
  147.         /* iterate through the remaining pixel groups (4 pixels/group) */
  148.         pixel_groups = s->width / 4 - 1;
  149.         while (pixel_groups--) {
  150.  
  151.             cur_byte = buf[stream_ptr++];
  152.             u_pred += u_table[(cur_byte & 0xF0) >> 4];
  153.             u_plane[u_ptr++] = u_pred;
  154.             y_pred += y_table[cur_byte & 0x0F];
  155.             y_plane[y_ptr++] = y_pred;
  156.  
  157.             cur_byte = buf[stream_ptr++];
  158.             v_pred += v_table[(cur_byte & 0xF0) >> 4];
  159.             v_plane[v_ptr++] = v_pred;
  160.             y_pred += y_table[cur_byte & 0x0F];
  161.             y_plane[y_ptr++] = y_pred;
  162.  
  163.             cur_byte = buf[stream_ptr++];
  164.             y_pred += y_table[cur_byte & 0x0F];
  165.             y_plane[y_ptr++] = y_pred;
  166.             y_pred += y_table[(cur_byte & 0xF0) >> 4];
  167.             y_plane[y_ptr++] = y_pred;
  168.  
  169.         }
  170.     }
  171.     }
  172.  
  173.     *got_frame = 1;
  174.  
  175.     return buf_size;
  176. }
  177.  
  178. #if CONFIG_AURA_DECODER
  179. AVCodec ff_aura_decoder = {
  180.     .name           = "aura",
  181.     .long_name      = NULL_IF_CONFIG_SMALL("Auravision AURA"),
  182.     .type           = AVMEDIA_TYPE_VIDEO,
  183.     .id             = AV_CODEC_ID_AURA,
  184.     .priv_data_size = sizeof(CyuvDecodeContext),
  185.     .init           = cyuv_decode_init,
  186.     .decode         = cyuv_decode_frame,
  187.     .capabilities   = CODEC_CAP_DR1,
  188. };
  189. #endif
  190.  
  191. #if CONFIG_CYUV_DECODER
  192. AVCodec ff_cyuv_decoder = {
  193.     .name           = "cyuv",
  194.     .long_name      = NULL_IF_CONFIG_SMALL("Creative YUV (CYUV)"),
  195.     .type           = AVMEDIA_TYPE_VIDEO,
  196.     .id             = AV_CODEC_ID_CYUV,
  197.     .priv_data_size = sizeof(CyuvDecodeContext),
  198.     .init           = cyuv_decode_init,
  199.     .decode         = cyuv_decode_frame,
  200.     .capabilities   = CODEC_CAP_DR1,
  201. };
  202. #endif
  203.