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libavcodec/eatqi.c

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00001 /*
00002  * Electronic Arts TQI Video Decoder
00003  * Copyright (c) 2007-2009 Peter Ross <pross@xvid.org>
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg 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  * FFmpeg 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 FFmpeg; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
00020  */
00021 
00031 #include "avcodec.h"
00032 #include "get_bits.h"
00033 #include "dsputil.h"
00034 #include "aandcttab.h"
00035 #include "mpeg12.h"
00036 #include "mpegvideo.h"
00037 
00038 typedef struct TqiContext {
00039     MpegEncContext s;
00040     AVFrame frame;
00041     void *bitstream_buf;
00042     unsigned int bitstream_buf_size;
00043     DECLARE_ALIGNED(16, DCTELEM, block)[6][64];
00044 } TqiContext;
00045 
00046 static av_cold int tqi_decode_init(AVCodecContext *avctx)
00047 {
00048     TqiContext *t = avctx->priv_data;
00049     MpegEncContext *s = &t->s;
00050     s->avctx = avctx;
00051     if(avctx->idct_algo==FF_IDCT_AUTO)
00052         avctx->idct_algo=FF_IDCT_EA;
00053     dsputil_init(&s->dsp, avctx);
00054     ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable, ff_zigzag_direct);
00055     s->qscale = 1;
00056     avctx->time_base = (AVRational){1, 15};
00057     avctx->pix_fmt = PIX_FMT_YUV420P;
00058     ff_mpeg12_init_vlcs();
00059     return 0;
00060 }
00061 
00062 static void tqi_decode_mb(MpegEncContext *s, DCTELEM (*block)[64])
00063 {
00064     int n;
00065     s->dsp.clear_blocks(block[0]);
00066     for (n=0; n<6; n++)
00067         ff_mpeg1_decode_block_intra(s, block[n], n);
00068 }
00069 
00070 static inline void tqi_idct_put(TqiContext *t, DCTELEM (*block)[64])
00071 {
00072     MpegEncContext *s = &t->s;
00073     int linesize= t->frame.linesize[0];
00074     uint8_t *dest_y  = t->frame.data[0] + (s->mb_y * 16* linesize            ) + s->mb_x * 16;
00075     uint8_t *dest_cb = t->frame.data[1] + (s->mb_y * 8 * t->frame.linesize[1]) + s->mb_x * 8;
00076     uint8_t *dest_cr = t->frame.data[2] + (s->mb_y * 8 * t->frame.linesize[2]) + s->mb_x * 8;
00077 
00078     s->dsp.idct_put(dest_y                 , linesize, block[0]);
00079     s->dsp.idct_put(dest_y              + 8, linesize, block[1]);
00080     s->dsp.idct_put(dest_y + 8*linesize    , linesize, block[2]);
00081     s->dsp.idct_put(dest_y + 8*linesize + 8, linesize, block[3]);
00082     if(!(s->avctx->flags&CODEC_FLAG_GRAY)) {
00083         s->dsp.idct_put(dest_cb, t->frame.linesize[1], block[4]);
00084         s->dsp.idct_put(dest_cr, t->frame.linesize[2], block[5]);
00085     }
00086 }
00087 
00088 static void tqi_calculate_qtable(MpegEncContext *s, int quant)
00089 {
00090     const int qscale = (215 - 2*quant)*5;
00091     int i;
00092     if (s->avctx->idct_algo==FF_IDCT_EA) {
00093         s->intra_matrix[0] = (ff_inv_aanscales[0]*ff_mpeg1_default_intra_matrix[0])>>11;
00094         for(i=1; i<64; i++)
00095             s->intra_matrix[i] = (ff_inv_aanscales[i]*ff_mpeg1_default_intra_matrix[i]*qscale + 32)>>14;
00096     }else{
00097         s->intra_matrix[0] = ff_mpeg1_default_intra_matrix[0];
00098         for(i=1; i<64; i++)
00099             s->intra_matrix[i] = (ff_mpeg1_default_intra_matrix[i]*qscale + 32)>>3;
00100     }
00101 }
00102 
00103 static int tqi_decode_frame(AVCodecContext *avctx,
00104                             void *data, int *data_size,
00105                             AVPacket *avpkt)
00106 {
00107     const uint8_t *buf = avpkt->data;
00108     int buf_size = avpkt->size;
00109     const uint8_t *buf_end = buf+buf_size;
00110     TqiContext *t = avctx->priv_data;
00111     MpegEncContext *s = &t->s;
00112 
00113     s->width  = AV_RL16(&buf[0]);
00114     s->height = AV_RL16(&buf[2]);
00115     tqi_calculate_qtable(s, buf[4]);
00116     buf += 8;
00117 
00118     if (t->frame.data[0])
00119         avctx->release_buffer(avctx, &t->frame);
00120 
00121     if (s->avctx->width!=s->width || s->avctx->height!=s->height)
00122         avcodec_set_dimensions(s->avctx, s->width, s->height);
00123 
00124     if(avctx->get_buffer(avctx, &t->frame) < 0) {
00125         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
00126         return -1;
00127     }
00128 
00129     av_fast_malloc(&t->bitstream_buf, &t->bitstream_buf_size, (buf_end-buf) + FF_INPUT_BUFFER_PADDING_SIZE);
00130     if (!t->bitstream_buf)
00131         return AVERROR(ENOMEM);
00132     s->dsp.bswap_buf(t->bitstream_buf, (const uint32_t*)buf, (buf_end-buf)/4);
00133     init_get_bits(&s->gb, t->bitstream_buf, 8*(buf_end-buf));
00134 
00135     s->last_dc[0] = s->last_dc[1] = s->last_dc[2] = 0;
00136     for (s->mb_y=0; s->mb_y<(avctx->height+15)/16; s->mb_y++)
00137     for (s->mb_x=0; s->mb_x<(avctx->width+15)/16; s->mb_x++)
00138     {
00139         tqi_decode_mb(s, t->block);
00140         tqi_idct_put(t, t->block);
00141     }
00142 
00143     *data_size = sizeof(AVFrame);
00144     *(AVFrame*)data = t->frame;
00145     return buf_size;
00146 }
00147 
00148 static av_cold int tqi_decode_end(AVCodecContext *avctx)
00149 {
00150     TqiContext *t = avctx->priv_data;
00151     if(t->frame.data[0])
00152         avctx->release_buffer(avctx, &t->frame);
00153     av_free(t->bitstream_buf);
00154     return 0;
00155 }
00156 
00157 AVCodec eatqi_decoder = {
00158     "eatqi",
00159     AVMEDIA_TYPE_VIDEO,
00160     CODEC_ID_TQI,
00161     sizeof(TqiContext),
00162     tqi_decode_init,
00163     NULL,
00164     tqi_decode_end,
00165     tqi_decode_frame,
00166     CODEC_CAP_DR1,
00167     .long_name = NULL_IF_CONFIG_SMALL("Electronic Arts TQI Video"),
00168 };

Generated on Fri Sep 16 2011 17:17:36 for FFmpeg by  doxygen 1.7.1