/*
- * Common AAC and AC3 parser
- * Copyright (c) 2003 Fabrice Bellard.
- * Copyright (c) 2003 Michael Niedermayer.
+ * Common AAC and AC-3 parser
+ * Copyright (c) 2003 Fabrice Bellard
+ * Copyright (c) 2003 Michael Niedermayer
*
* This file is part of FFmpeg.
*
const uint8_t *buf, int buf_size)
{
AACAC3ParseContext *s = s1->priv_data;
- const uint8_t *buf_ptr;
- int len, sample_rate, bit_rate, channels, samples;
+ ParseContext *pc = &s->pc;
+ int len, i;
+ int new_frame_start;
- *poutbuf = NULL;
- *poutbuf_size = 0;
-
- buf_ptr = buf;
- while (buf_size > 0) {
- int size_needed= s->frame_size ? s->frame_size : s->header_size;
- len = s->inbuf_ptr - s->inbuf;
-
- if(len<size_needed){
- len = FFMIN(size_needed - len, buf_size);
- memcpy(s->inbuf_ptr, buf_ptr, len);
- buf_ptr += len;
- s->inbuf_ptr += len;
- buf_size -= len;
- }
-
- if (s->frame_size == 0) {
- if ((s->inbuf_ptr - s->inbuf) == s->header_size) {
- len = s->sync(s->inbuf, &channels, &sample_rate, &bit_rate,
- &samples);
- if (len == 0) {
- /* no sync found : move by one byte (inefficient, but simple!) */
- memmove(s->inbuf, s->inbuf + 1, s->header_size - 1);
- s->inbuf_ptr--;
- } else {
- s->frame_size = len;
- /* update codec info */
- avctx->sample_rate = sample_rate;
- avctx->channels = channels;
- avctx->bit_rate = bit_rate;
- avctx->frame_size = samples;
- }
+get_next:
+ i=END_NOT_FOUND;
+ if(s->remaining_size <= buf_size){
+ if(s->remaining_size && !s->need_next_header){
+ i= s->remaining_size;
+ s->remaining_size = 0;
+ }else{ //we need a header first
+ len=0;
+ for(i=s->remaining_size; i<buf_size; i++){
+ s->state = (s->state<<8) + buf[i];
+ if((len=s->sync(s->state, s, &s->need_next_header, &new_frame_start)))
+ break;
}
- } else {
- if(s->inbuf_ptr - s->inbuf == s->frame_size){
- *poutbuf = s->inbuf;
- *poutbuf_size = s->frame_size;
- s->inbuf_ptr = s->inbuf;
- s->frame_size = 0;
- break;
+ if(len<=0){
+ i=END_NOT_FOUND;
+ }else{
+ s->state=0;
+ i-= s->header_size -1;
+ s->remaining_size = len;
+ if(!new_frame_start || pc->index+i<=0){
+ s->remaining_size += i;
+ goto get_next;
+ }
}
}
}
- return buf_ptr - buf;
+
+ if(ff_combine_frame(pc, i, &buf, &buf_size)<0){
+ s->remaining_size -= FFMIN(s->remaining_size, buf_size);
+ *poutbuf = NULL;
+ *poutbuf_size = 0;
+ return buf_size;
+ }
+
+ *poutbuf = buf;
+ *poutbuf_size = buf_size;
+
+ /* update codec info */
+ avctx->sample_rate = s->sample_rate;
+ if(s->codec_id)
+ avctx->codec_id = s->codec_id;
+
+ /* allow downmixing to stereo (or mono for AC-3) */
+ if(avctx->request_channels > 0 &&
+ avctx->request_channels < s->channels &&
+ (avctx->request_channels <= 2 ||
+ (avctx->request_channels == 1 &&
+ (avctx->codec_id == CODEC_ID_AC3 ||
+ avctx->codec_id == CODEC_ID_EAC3)))) {
+ avctx->channels = avctx->request_channels;
+ } else if (avctx->codec_id != CODEC_ID_AAC || s->channels) {
+ avctx->channels = s->channels;
+ avctx->channel_layout = s->channel_layout;
+ }
+ avctx->bit_rate = s->bit_rate;
+ avctx->frame_size = s->samples;
+
+ return i;
}