FFmpeg: libavcodec/roqvideodec.c Source File

00001 /*
00002  * Copyright (C) 2003 the ffmpeg project
00003  *
00004  * This file is part of FFmpeg.
00005  *
00006  * FFmpeg is free software; you can redistribute it and/or
00007  * modify it under the terms of the GNU Lesser General Public
00008  * License as published by the Free Software Foundation; either
00009  * version 2.1 of the License, or (at your option) any later version.
00010  *
00011  * FFmpeg is distributed in the hope that it will be useful,
00012  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00013  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00014  * Lesser General Public License for more details.
00015  *
00016  * You should have received a copy of the GNU Lesser General Public
00017  * License along with FFmpeg; if not, write to the Free Software
00018  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00019  */
00020 
00028 #include <stdio.h>
00029 #include <stdlib.h>
00030 #include <string.h>
00031 
00032 #include "avcodec.h"
00033 #include "bytestream.h"
00034 #include "roqvideo.h"
00035 
00036 static void roqvideo_decode_frame(RoqContext *ri)
00037 {
00038     unsigned int chunk_id = 0, chunk_arg = 0;
00039     unsigned long chunk_size = 0;
00040     int i, j, k, nv1, nv2, vqflg = 0, vqflg_pos = -1;
00041     int vqid, bpos, xpos, ypos, xp, yp, x, y, mx, my;
00042     int frame_stats[2][4] = {{0},{0}};
00043     roq_qcell *qcell;
00044     const unsigned char *buf = ri->buf;
00045     const unsigned char *buf_end = ri->buf + ri->size;
00046 
00047     while (buf < buf_end) {
00048         chunk_id = bytestream_get_le16(&buf);
00049         chunk_size = bytestream_get_le32(&buf);
00050         chunk_arg = bytestream_get_le16(&buf);
00051 
00052         if(chunk_id == RoQ_QUAD_VQ)
00053             break;
00054         if(chunk_id == RoQ_QUAD_CODEBOOK) {
00055             if((nv1 = chunk_arg >> 8) == 0)
00056                 nv1 = 256;
00057             if((nv2 = chunk_arg & 0xff) == 0 && nv1 * 6 < chunk_size)
00058                 nv2 = 256;
00059             for(i = 0; i < nv1; i++) {
00060                 ri->cb2x2[i].y[0] = *buf++;
00061                 ri->cb2x2[i].y[1] = *buf++;
00062                 ri->cb2x2[i].y[2] = *buf++;
00063                 ri->cb2x2[i].y[3] = *buf++;
00064                 ri->cb2x2[i].u = *buf++;
00065                 ri->cb2x2[i].v = *buf++;
00066             }
00067             for(i = 0; i < nv2; i++)
00068                 for(j = 0; j < 4; j++)
00069                     ri->cb4x4[i].idx[j] = *buf++;
00070         }
00071     }
00072 
00073     bpos = xpos = ypos = 0;
00074     if (chunk_size > buf_end - buf) {
00075         av_log(ri->avctx, AV_LOG_ERROR, "Chunk does not fit in input buffer\n");
00076         chunk_size = buf_end - buf;
00077     }
00078     while(bpos < chunk_size) {
00079         for (yp = ypos; yp < ypos + 16; yp += 8)
00080             for (xp = xpos; xp < xpos + 16; xp += 8) {
00081                 if (bpos >= chunk_size) {
00082                     av_log(ri->avctx, AV_LOG_ERROR, "Input buffer too small\n");
00083                     return;
00084                 }
00085                 if (vqflg_pos < 0) {
00086                     vqflg = buf[bpos++]; vqflg |= (buf[bpos++] << 8);
00087                     vqflg_pos = 7;
00088                 }
00089                 vqid = (vqflg >> (vqflg_pos * 2)) & 0x3;
00090                 frame_stats[0][vqid]++;
00091                 vqflg_pos--;
00092 
00093                 switch(vqid) {
00094                 case RoQ_ID_MOT:
00095                     break;
00096                 case RoQ_ID_FCC:
00097                     mx = 8 - (buf[bpos] >> 4) - ((signed char) (chunk_arg >> 8));
00098                     my = 8 - (buf[bpos++] & 0xf) - ((signed char) chunk_arg);
00099                     ff_apply_motion_8x8(ri, xp, yp, mx, my);
00100                     break;
00101                 case RoQ_ID_SLD:
00102                     qcell = ri->cb4x4 + buf[bpos++];
00103                     ff_apply_vector_4x4(ri, xp, yp, ri->cb2x2 + qcell->idx[0]);
00104                     ff_apply_vector_4x4(ri, xp+4, yp, ri->cb2x2 + qcell->idx[1]);
00105                     ff_apply_vector_4x4(ri, xp, yp+4, ri->cb2x2 + qcell->idx[2]);
00106                     ff_apply_vector_4x4(ri, xp+4, yp+4, ri->cb2x2 + qcell->idx[3]);
00107                     break;
00108                 case RoQ_ID_CCC:
00109                     for (k = 0; k < 4; k++) {
00110                         x = xp; y = yp;
00111                         if(k & 0x01) x += 4;
00112                         if(k & 0x02) y += 4;
00113 
00114                         if (bpos >= chunk_size) {
00115                             av_log(ri->avctx, AV_LOG_ERROR, "Input buffer too small\n");
00116                             return;
00117                         }
00118                         if (vqflg_pos < 0) {
00119                             vqflg = buf[bpos++];
00120                             vqflg |= (buf[bpos++] << 8);
00121                             vqflg_pos = 7;
00122                         }
00123                         vqid = (vqflg >> (vqflg_pos * 2)) & 0x3;
00124                         frame_stats[1][vqid]++;
00125                         vqflg_pos--;
00126                         switch(vqid) {
00127                         case RoQ_ID_MOT:
00128                             break;
00129                         case RoQ_ID_FCC:
00130                             mx = 8 - (buf[bpos] >> 4) - ((signed char) (chunk_arg >> 8));
00131                             my = 8 - (buf[bpos++] & 0xf) - ((signed char) chunk_arg);
00132                             ff_apply_motion_4x4(ri, x, y, mx, my);
00133                             break;
00134                         case RoQ_ID_SLD:
00135                             qcell = ri->cb4x4 + buf[bpos++];
00136                             ff_apply_vector_2x2(ri, x, y, ri->cb2x2 + qcell->idx[0]);
00137                             ff_apply_vector_2x2(ri, x+2, y, ri->cb2x2 + qcell->idx[1]);
00138                             ff_apply_vector_2x2(ri, x, y+2, ri->cb2x2 + qcell->idx[2]);
00139                             ff_apply_vector_2x2(ri, x+2, y+2, ri->cb2x2 + qcell->idx[3]);
00140                             break;
00141                         case RoQ_ID_CCC:
00142                             ff_apply_vector_2x2(ri, x, y, ri->cb2x2 + buf[bpos]);
00143                             ff_apply_vector_2x2(ri, x+2, y, ri->cb2x2 + buf[bpos+1]);
00144                             ff_apply_vector_2x2(ri, x, y+2, ri->cb2x2 + buf[bpos+2]);
00145                             ff_apply_vector_2x2(ri, x+2, y+2, ri->cb2x2 + buf[bpos+3]);
00146                             bpos += 4;
00147                             break;
00148                         }
00149                     }
00150                     break;
00151                 default:
00152                     av_log(ri->avctx, AV_LOG_ERROR, "Unknown vq code: %d\n", vqid);
00153             }
00154         }
00155 
00156         xpos += 16;
00157         if (xpos >= ri->width) {
00158             xpos -= ri->width;
00159             ypos += 16;
00160         }
00161         if(ypos >= ri->height)
00162             break;
00163     }
00164 }
00165 
00166 
00167 static av_cold int roq_decode_init(AVCodecContext *avctx)
00168 {
00169     RoqContext *s = avctx->priv_data;
00170 
00171     s->avctx = avctx;
00172     s->width = avctx->width;
00173     s->height = avctx->height;
00174     avcodec_get_frame_defaults(&s->frames[0]);
00175     avcodec_get_frame_defaults(&s->frames[1]);
00176     s->last_frame    = &s->frames[0];
00177     s->current_frame = &s->frames[1];
00178     avctx->pix_fmt = PIX_FMT_YUV444P;
00179 
00180     return 0;
00181 }
00182 
00183 static int roq_decode_frame(AVCodecContext *avctx,
00184                             void *data, int *data_size,
00185                             AVPacket *avpkt)
00186 {
00187     const uint8_t *buf = avpkt->data;
00188     int buf_size = avpkt->size;
00189     RoqContext *s = avctx->priv_data;
00190     int copy= !s->current_frame->data[0];
00191 
00192     s->current_frame->reference = 3;
00193     if (avctx->reget_buffer(avctx, s->current_frame)) {
00194         av_log(avctx, AV_LOG_ERROR, "  RoQ: get_buffer() failed\n");
00195         return -1;
00196     }
00197 
00198     if(copy)
00199         av_picture_copy((AVPicture*)s->current_frame, (AVPicture*)s->last_frame,
00200                         avctx->pix_fmt, avctx->width, avctx->height);
00201 
00202     s->buf = buf;
00203     s->size = buf_size;
00204     roqvideo_decode_frame(s);
00205 
00206     *data_size = sizeof(AVFrame);
00207     *(AVFrame*)data = *s->current_frame;
00208 
00209     /* shuffle frames */
00210     FFSWAP(AVFrame *, s->current_frame, s->last_frame);
00211 
00212     return buf_size;
00213 }
00214 
00215 static av_cold int roq_decode_end(AVCodecContext *avctx)
00216 {
00217     RoqContext *s = avctx->priv_data;
00218 
00219     /* release the last frame */
00220     if (s->last_frame->data[0])
00221         avctx->release_buffer(avctx, s->last_frame);
00222     if (s->current_frame->data[0])
00223         avctx->release_buffer(avctx, s->current_frame);
00224 
00225     return 0;
00226 }
00227 
00228 AVCodec ff_roq_decoder = {
00229     .name           = "roqvideo",
00230     .type           = AVMEDIA_TYPE_VIDEO,
00231     .id             = CODEC_ID_ROQ,
00232     .priv_data_size = sizeof(RoqContext),
00233     .init           = roq_decode_init,
00234     .close          = roq_decode_end,
00235     .decode         = roq_decode_frame,
00236     .capabilities   = CODEC_CAP_DR1,
00237     .long_name = NULL_IF_CONFIG_SMALL("id RoQ video"),
00238 };