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libavcodec/roqvideodec.c

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00001 /*
00002  * Copyright (C) 2003 the ffmpeg project
00003  *
00004  * This file is part of Libav.
00005  *
00006  * Libav 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  * Libav 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 Libav; 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, xpos, ypos, xp, yp, x, y, mx, my;
00042     int frame_stats[2][4] = {{0},{0}};
00043     roq_qcell *qcell;
00044     int64_t chunk_start;
00045 
00046     while (bytestream2_get_bytes_left(&ri->gb) > 0) {
00047         chunk_id = bytestream2_get_le16(&ri->gb);
00048         chunk_size = bytestream2_get_le32(&ri->gb);
00049         chunk_arg = bytestream2_get_le16(&ri->gb);
00050 
00051         if(chunk_id == RoQ_QUAD_VQ)
00052             break;
00053         if(chunk_id == RoQ_QUAD_CODEBOOK) {
00054             if((nv1 = chunk_arg >> 8) == 0)
00055                 nv1 = 256;
00056             if((nv2 = chunk_arg & 0xff) == 0 && nv1 * 6 < chunk_size)
00057                 nv2 = 256;
00058             for(i = 0; i < nv1; i++) {
00059                 ri->cb2x2[i].y[0] = bytestream2_get_byte(&ri->gb);
00060                 ri->cb2x2[i].y[1] = bytestream2_get_byte(&ri->gb);
00061                 ri->cb2x2[i].y[2] = bytestream2_get_byte(&ri->gb);
00062                 ri->cb2x2[i].y[3] = bytestream2_get_byte(&ri->gb);
00063                 ri->cb2x2[i].u = bytestream2_get_byte(&ri->gb);
00064                 ri->cb2x2[i].v = bytestream2_get_byte(&ri->gb);
00065             }
00066             for(i = 0; i < nv2; i++)
00067                 for(j = 0; j < 4; j++)
00068                     ri->cb4x4[i].idx[j] = bytestream2_get_byte(&ri->gb);
00069         }
00070     }
00071 
00072     chunk_start = bytestream2_tell(&ri->gb);
00073     xpos = ypos = 0;
00074     while (bytestream2_tell(&ri->gb) < chunk_start + chunk_size) {
00075         for (yp = ypos; yp < ypos + 16; yp += 8)
00076             for (xp = xpos; xp < xpos + 16; xp += 8) {
00077                 if (vqflg_pos < 0) {
00078                     vqflg = bytestream2_get_le16(&ri->gb);
00079                     vqflg_pos = 7;
00080                 }
00081                 vqid = (vqflg >> (vqflg_pos * 2)) & 0x3;
00082                 frame_stats[0][vqid]++;
00083                 vqflg_pos--;
00084 
00085                 switch(vqid) {
00086                 case RoQ_ID_MOT:
00087                     break;
00088                 case RoQ_ID_FCC: {
00089                     int byte = bytestream2_get_byte(&ri->gb);
00090                     mx = 8 - (byte >> 4) - ((signed char) (chunk_arg >> 8));
00091                     my = 8 - (byte & 0xf) - ((signed char) chunk_arg);
00092                     ff_apply_motion_8x8(ri, xp, yp, mx, my);
00093                     break;
00094                 }
00095                 case RoQ_ID_SLD:
00096                     qcell = ri->cb4x4 + bytestream2_get_byte(&ri->gb);
00097                     ff_apply_vector_4x4(ri, xp, yp, ri->cb2x2 + qcell->idx[0]);
00098                     ff_apply_vector_4x4(ri, xp+4, yp, ri->cb2x2 + qcell->idx[1]);
00099                     ff_apply_vector_4x4(ri, xp, yp+4, ri->cb2x2 + qcell->idx[2]);
00100                     ff_apply_vector_4x4(ri, xp+4, yp+4, ri->cb2x2 + qcell->idx[3]);
00101                     break;
00102                 case RoQ_ID_CCC:
00103                     for (k = 0; k < 4; k++) {
00104                         x = xp; y = yp;
00105                         if(k & 0x01) x += 4;
00106                         if(k & 0x02) y += 4;
00107 
00108                         if (vqflg_pos < 0) {
00109                             vqflg = bytestream2_get_le16(&ri->gb);
00110                             vqflg_pos = 7;
00111                         }
00112                         vqid = (vqflg >> (vqflg_pos * 2)) & 0x3;
00113                         frame_stats[1][vqid]++;
00114                         vqflg_pos--;
00115                         switch(vqid) {
00116                         case RoQ_ID_MOT:
00117                             break;
00118                         case RoQ_ID_FCC: {
00119                             int byte = bytestream2_get_byte(&ri->gb);
00120                             mx = 8 - (byte >> 4) - ((signed char) (chunk_arg >> 8));
00121                             my = 8 - (byte & 0xf) - ((signed char) chunk_arg);
00122                             ff_apply_motion_4x4(ri, x, y, mx, my);
00123                             break;
00124                         }
00125                         case RoQ_ID_SLD:
00126                             qcell = ri->cb4x4 + bytestream2_get_byte(&ri->gb);
00127                             ff_apply_vector_2x2(ri, x, y, ri->cb2x2 + qcell->idx[0]);
00128                             ff_apply_vector_2x2(ri, x+2, y, ri->cb2x2 + qcell->idx[1]);
00129                             ff_apply_vector_2x2(ri, x, y+2, ri->cb2x2 + qcell->idx[2]);
00130                             ff_apply_vector_2x2(ri, x+2, y+2, ri->cb2x2 + qcell->idx[3]);
00131                             break;
00132                         case RoQ_ID_CCC:
00133                             ff_apply_vector_2x2(ri, x, y, ri->cb2x2 + bytestream2_get_byte(&ri->gb));
00134                             ff_apply_vector_2x2(ri, x+2, y, ri->cb2x2 + bytestream2_get_byte(&ri->gb));
00135                             ff_apply_vector_2x2(ri, x, y+2, ri->cb2x2 + bytestream2_get_byte(&ri->gb));
00136                             ff_apply_vector_2x2(ri, x+2, y+2, ri->cb2x2 + bytestream2_get_byte(&ri->gb));
00137                             break;
00138                         }
00139                     }
00140                     break;
00141                 default:
00142                     av_log(ri->avctx, AV_LOG_ERROR, "Unknown vq code: %d\n", vqid);
00143             }
00144         }
00145 
00146         xpos += 16;
00147         if (xpos >= ri->width) {
00148             xpos -= ri->width;
00149             ypos += 16;
00150         }
00151         if(ypos >= ri->height)
00152             break;
00153     }
00154 }
00155 
00156 
00157 static av_cold int roq_decode_init(AVCodecContext *avctx)
00158 {
00159     RoqContext *s = avctx->priv_data;
00160 
00161     s->avctx = avctx;
00162     s->width = avctx->width;
00163     s->height = avctx->height;
00164     s->last_frame    = &s->frames[0];
00165     s->current_frame = &s->frames[1];
00166     avctx->pix_fmt = PIX_FMT_YUV444P;
00167 
00168     return 0;
00169 }
00170 
00171 static int roq_decode_frame(AVCodecContext *avctx,
00172                             void *data, int *data_size,
00173                             AVPacket *avpkt)
00174 {
00175     const uint8_t *buf = avpkt->data;
00176     int buf_size = avpkt->size;
00177     RoqContext *s = avctx->priv_data;
00178     int copy= !s->current_frame->data[0];
00179 
00180     s->current_frame->reference = 3;
00181     if (avctx->reget_buffer(avctx, s->current_frame)) {
00182         av_log(avctx, AV_LOG_ERROR, "  RoQ: get_buffer() failed\n");
00183         return -1;
00184     }
00185 
00186     if(copy)
00187         av_picture_copy((AVPicture*)s->current_frame, (AVPicture*)s->last_frame,
00188                         avctx->pix_fmt, avctx->width, avctx->height);
00189 
00190     bytestream2_init(&s->gb, buf, buf_size);
00191     roqvideo_decode_frame(s);
00192 
00193     *data_size = sizeof(AVFrame);
00194     *(AVFrame*)data = *s->current_frame;
00195 
00196     /* shuffle frames */
00197     FFSWAP(AVFrame *, s->current_frame, s->last_frame);
00198 
00199     return buf_size;
00200 }
00201 
00202 static av_cold int roq_decode_end(AVCodecContext *avctx)
00203 {
00204     RoqContext *s = avctx->priv_data;
00205 
00206     /* release the last frame */
00207     if (s->last_frame->data[0])
00208         avctx->release_buffer(avctx, s->last_frame);
00209     if (s->current_frame->data[0])
00210         avctx->release_buffer(avctx, s->current_frame);
00211 
00212     return 0;
00213 }
00214 
00215 AVCodec ff_roq_decoder = {
00216     .name           = "roqvideo",
00217     .type           = AVMEDIA_TYPE_VIDEO,
00218     .id             = CODEC_ID_ROQ,
00219     .priv_data_size = sizeof(RoqContext),
00220     .init           = roq_decode_init,
00221     .close          = roq_decode_end,
00222     .decode         = roq_decode_frame,
00223     .capabilities   = CODEC_CAP_DR1,
00224     .long_name = NULL_IF_CONFIG_SMALL("id RoQ video"),
00225 };
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