libavcodec/sp5xdec.c

   1 /*
   2  * Sunplus JPEG decoder (SP5X)
   3  * Copyright (c) 2003 Alex Beregszaszi
   4  *
   5  * This file is part of Libav.
   6  *
   7  * Libav is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * Libav is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with Libav; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 /**
  23  * @file
  24  * Sunplus JPEG decoder (SP5X).
  25  */
  26
  27 #include "avcodec.h"
  28 #include "mjpeg.h"
  29 #include "mjpegdec.h"
  30 #include "sp5x.h"
  31
  32
  33 static int sp5x_decode_frame(AVCodecContext *avctx,
  34                               void *data, int *got_frame,
  35                               AVPacket *avpkt)
  36 {
  37     const uint8_t *buf = avpkt->data;
  38     int buf_size = avpkt->size;
  39     AVPacket avpkt_recoded;
  40     const int qscale = 5;
  41     uint8_t *recoded;
  42     int i = 0, j = 0;
  43
  44     if (!avctx->width || !avctx->height)
  45         return -1;
  46
  47     recoded = av_mallocz(buf_size + 1024);
  48     if (!recoded)
  49         return -1;
  50
  51     /* SOI */
  52     recoded[j++] = 0xFF;
  53     recoded[j++] = 0xD8;
  54
  55     memcpy(recoded+j, &sp5x_data_dqt[0], sizeof(sp5x_data_dqt));
  56     memcpy(recoded+j+5, &sp5x_quant_table[qscale * 2], 64);
  57     memcpy(recoded+j+70, &sp5x_quant_table[(qscale * 2) + 1], 64);
  58     j += sizeof(sp5x_data_dqt);
  59
  60     memcpy(recoded+j, &sp5x_data_dht[0], sizeof(sp5x_data_dht));
  61     j += sizeof(sp5x_data_dht);
  62
  63     memcpy(recoded+j, &sp5x_data_sof[0], sizeof(sp5x_data_sof));
  64     AV_WB16(recoded+j+5, avctx->coded_height);
  65     AV_WB16(recoded+j+7, avctx->coded_width);
  66     j += sizeof(sp5x_data_sof);
  67
  68     memcpy(recoded+j, &sp5x_data_sos[0], sizeof(sp5x_data_sos));
  69     j += sizeof(sp5x_data_sos);
  70
  71     if(avctx->codec_id==AV_CODEC_ID_AMV)
  72         for (i = 2; i < buf_size-2 && j < buf_size+1024-2; i++)
  73             recoded[j++] = buf[i];
  74     else
  75     for (i = 14; i < buf_size && j < buf_size+1024-2; i++)
  76     {
  77         recoded[j++] = buf[i];
  78         if (buf[i] == 0xff)
  79             recoded[j++] = 0;
  80     }
  81
  82     /* EOI */
  83     recoded[j++] = 0xFF;
  84     recoded[j++] = 0xD9;
  85
  86     av_init_packet(&avpkt_recoded);
  87     avpkt_recoded.data = recoded;
  88     avpkt_recoded.size = j;
  89     i = ff_mjpeg_decode_frame(avctx, data, got_frame, &avpkt_recoded);
  90
  91     av_free(recoded);
  92
  93     return i;
  94 }
  95
  96 AVCodec ff_sp5x_decoder = {
  97     .name           = "sp5x",
  98     .type           = AVMEDIA_TYPE_VIDEO,
  99     .id             = AV_CODEC_ID_SP5X,
 100     .priv_data_size = sizeof(MJpegDecodeContext),
 101     .init           = ff_mjpeg_decode_init,
 102     .close          = ff_mjpeg_decode_end,
 103     .decode         = sp5x_decode_frame,
 104     .capabilities   = CODEC_CAP_DR1,
 105     .long_name      = NULL_IF_CONFIG_SMALL("Sunplus JPEG (SP5X)"),
 106 };
 107
 108 AVCodec ff_amv_decoder = {
 109     .name           = "amv",
 110     .type           = AVMEDIA_TYPE_VIDEO,
 111     .id             = AV_CODEC_ID_AMV,
 112     .priv_data_size = sizeof(MJpegDecodeContext),
 113     .init           = ff_mjpeg_decode_init,
 114     .close          = ff_mjpeg_decode_end,
 115     .decode         = sp5x_decode_frame,
 116     .long_name      = NULL_IF_CONFIG_SMALL("AMV Video"),
 117 };