ffv1: refactor slice decoding init loop so that the first is less a special case

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This commit is contained in:
Michael Niedermayer 2012-04-20 14:57:03 +02:00
parent 8456089f50
commit 9408316a85

View File

@ -1862,28 +1862,31 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPac
if(avctx->debug&FF_DEBUG_PICT_INFO)
av_log(avctx, AV_LOG_ERROR, "keyframe:%d coder:%d\n", p->key_frame, f->ac);
if(!f->ac){
bytes_read = c->bytestream - c->bytestream_start - 1;
if(bytes_read ==0) av_log(avctx, AV_LOG_ERROR, "error at end of AC stream\n"); //FIXME
//printf("pos=%d\n", bytes_read);
init_get_bits(&f->slice_context[0]->gb, buf + bytes_read, (buf_size - bytes_read) * 8);
} else {
bytes_read = 0; /* avoid warning */
}
buf_p= buf + buf_size;
for(i=f->slice_count-1; i>0; i--){
for(i=f->slice_count-1; i>=0; i--){
FFV1Context *fs= f->slice_context[i];
int v= AV_RB24(buf_p-3)+3;
if(buf_p - buf <= v){
int v;
if(i) v = AV_RB24(buf_p-3)+3;
else v = buf_p - c->bytestream_start;
if(buf_p - c->bytestream_start < v){
av_log(avctx, AV_LOG_ERROR, "Slice pointer chain broken\n");
return -1;
}
buf_p -= v;
if(fs->ac){
ff_init_range_decoder(&fs->c, buf_p, v);
if(i){
if(fs->ac){
ff_init_range_decoder(&fs->c, buf_p, v);
}else{
init_get_bits(&fs->gb, buf_p, v * 8);
}
}else{
init_get_bits(&fs->gb, buf_p, v * 8);
if(!f->ac){
bytes_read = c->bytestream - c->bytestream_start - 1;
if(bytes_read ==0) av_log(avctx, AV_LOG_ERROR, "error at end of AC stream\n"); //FIXME
init_get_bits(&fs->gb, buf + bytes_read, (buf_size - bytes_read) * 8);
}
}
}