• Main Page
  • Related Pages
  • Modules
  • Data Structures
  • Files
  • Examples
  • File List
  • Globals

libavcodec/eatqi.c

Go to the documentation of this file.
00001 /*
00002  * Electronic Arts TQI Video Decoder
00003  * Copyright (c) 2007-2009 Peter Ross <pross@xvid.org>
00004  *
00005  * This file is part of Libav.
00006  *
00007  * Libav is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * Libav is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with Libav; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
00020  */
00021 
00029 #include "avcodec.h"
00030 #include "get_bits.h"
00031 #include "dsputil.h"
00032 #include "aandcttab.h"
00033 #include "mpeg12.h"
00034 #include "mpegvideo.h"
00035 
00036 typedef struct TqiContext {
00037     MpegEncContext s;
00038     AVFrame frame;
00039     void *bitstream_buf;
00040     unsigned int bitstream_buf_size;
00041     DECLARE_ALIGNED(16, DCTELEM, block)[6][64];
00042 } TqiContext;
00043 
00044 static av_cold int tqi_decode_init(AVCodecContext *avctx)
00045 {
00046     TqiContext *t = avctx->priv_data;
00047     MpegEncContext *s = &t->s;
00048     s->avctx = avctx;
00049     if(avctx->idct_algo==FF_IDCT_AUTO)
00050         avctx->idct_algo=FF_IDCT_EA;
00051     dsputil_init(&s->dsp, avctx);
00052     ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable, ff_zigzag_direct);
00053     s->qscale = 1;
00054     avctx->time_base = (AVRational){1, 15};
00055     avctx->pix_fmt = PIX_FMT_YUV420P;
00056     ff_mpeg12_init_vlcs();
00057     return 0;
00058 }
00059 
00060 static void tqi_decode_mb(MpegEncContext *s, DCTELEM (*block)[64])
00061 {
00062     int n;
00063     s->dsp.clear_blocks(block[0]);
00064     for (n=0; n<6; n++)
00065         ff_mpeg1_decode_block_intra(s, block[n], n);
00066 }
00067 
00068 static inline void tqi_idct_put(TqiContext *t, DCTELEM (*block)[64])
00069 {
00070     MpegEncContext *s = &t->s;
00071     int linesize= t->frame.linesize[0];
00072     uint8_t *dest_y  = t->frame.data[0] + (s->mb_y * 16* linesize            ) + s->mb_x * 16;
00073     uint8_t *dest_cb = t->frame.data[1] + (s->mb_y * 8 * t->frame.linesize[1]) + s->mb_x * 8;
00074     uint8_t *dest_cr = t->frame.data[2] + (s->mb_y * 8 * t->frame.linesize[2]) + s->mb_x * 8;
00075 
00076     s->dsp.idct_put(dest_y                 , linesize, block[0]);
00077     s->dsp.idct_put(dest_y              + 8, linesize, block[1]);
00078     s->dsp.idct_put(dest_y + 8*linesize    , linesize, block[2]);
00079     s->dsp.idct_put(dest_y + 8*linesize + 8, linesize, block[3]);
00080     if(!(s->avctx->flags&CODEC_FLAG_GRAY)) {
00081         s->dsp.idct_put(dest_cb, t->frame.linesize[1], block[4]);
00082         s->dsp.idct_put(dest_cr, t->frame.linesize[2], block[5]);
00083     }
00084 }
00085 
00086 static void tqi_calculate_qtable(MpegEncContext *s, int quant)
00087 {
00088     const int qscale = (215 - 2*quant)*5;
00089     int i;
00090     if (s->avctx->idct_algo==FF_IDCT_EA) {
00091         s->intra_matrix[0] = (ff_inv_aanscales[0]*ff_mpeg1_default_intra_matrix[0])>>11;
00092         for(i=1; i<64; i++)
00093             s->intra_matrix[i] = (ff_inv_aanscales[i]*ff_mpeg1_default_intra_matrix[i]*qscale + 32)>>14;
00094     }else{
00095         s->intra_matrix[0] = ff_mpeg1_default_intra_matrix[0];
00096         for(i=1; i<64; i++)
00097             s->intra_matrix[i] = (ff_mpeg1_default_intra_matrix[i]*qscale + 32)>>3;
00098     }
00099 }
00100 
00101 static int tqi_decode_frame(AVCodecContext *avctx,
00102                             void *data, int *data_size,
00103                             AVPacket *avpkt)
00104 {
00105     const uint8_t *buf = avpkt->data;
00106     int buf_size = avpkt->size;
00107     const uint8_t *buf_end = buf+buf_size;
00108     TqiContext *t = avctx->priv_data;
00109     MpegEncContext *s = &t->s;
00110 
00111     s->width  = AV_RL16(&buf[0]);
00112     s->height = AV_RL16(&buf[2]);
00113     tqi_calculate_qtable(s, buf[4]);
00114     buf += 8;
00115 
00116     if (t->frame.data[0])
00117         avctx->release_buffer(avctx, &t->frame);
00118 
00119     if (s->avctx->width!=s->width || s->avctx->height!=s->height)
00120         avcodec_set_dimensions(s->avctx, s->width, s->height);
00121 
00122     if(avctx->get_buffer(avctx, &t->frame) < 0) {
00123         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
00124         return -1;
00125     }
00126 
00127     av_fast_malloc(&t->bitstream_buf, &t->bitstream_buf_size, (buf_end-buf) + FF_INPUT_BUFFER_PADDING_SIZE);
00128     if (!t->bitstream_buf)
00129         return AVERROR(ENOMEM);
00130     s->dsp.bswap_buf(t->bitstream_buf, (const uint32_t*)buf, (buf_end-buf)/4);
00131     init_get_bits(&s->gb, t->bitstream_buf, 8*(buf_end-buf));
00132 
00133     s->last_dc[0] = s->last_dc[1] = s->last_dc[2] = 0;
00134     for (s->mb_y=0; s->mb_y<(avctx->height+15)/16; s->mb_y++)
00135     for (s->mb_x=0; s->mb_x<(avctx->width+15)/16; s->mb_x++)
00136     {
00137         tqi_decode_mb(s, t->block);
00138         tqi_idct_put(t, t->block);
00139     }
00140 
00141     *data_size = sizeof(AVFrame);
00142     *(AVFrame*)data = t->frame;
00143     return buf_size;
00144 }
00145 
00146 static av_cold int tqi_decode_end(AVCodecContext *avctx)
00147 {
00148     TqiContext *t = avctx->priv_data;
00149     if(t->frame.data[0])
00150         avctx->release_buffer(avctx, &t->frame);
00151     av_free(t->bitstream_buf);
00152     return 0;
00153 }
00154 
00155 AVCodec ff_eatqi_decoder = {
00156     .name           = "eatqi",
00157     .type           = AVMEDIA_TYPE_VIDEO,
00158     .id             = CODEC_ID_TQI,
00159     .priv_data_size = sizeof(TqiContext),
00160     .init           = tqi_decode_init,
00161     .close          = tqi_decode_end,
00162     .decode         = tqi_decode_frame,
00163     .capabilities   = CODEC_CAP_DR1,
00164     .long_name = NULL_IF_CONFIG_SMALL("Electronic Arts TQI Video"),
00165 };
Generated on Sat Mar 17 2012 12:57:44 for Libav by doxygen 1.7.1