X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Faac_ac3_parser.c;h=f28f3f26782b382d15338878ce9759299a0354eb;hb=3ade5d56d0138e6069ea3e402c2c9ad050e347c0;hp=f384a0a3e829ab32ad9c0106fff0c3815b54d2ed;hpb=bd03aa1556ffeb490fc28794859acd8ef50abbe2;p=ffmpeg

diff --git a/libavcodec/aac_ac3_parser.c b/libavcodec/aac_ac3_parser.c
index f384a0a3e82..f28f3f26782 100644
--- a/libavcodec/aac_ac3_parser.c
+++ b/libavcodec/aac_ac3_parser.c
@@ -29,51 +29,60 @@ int ff_aac_ac3_parse(AVCodecParserContext *s1,
                      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{
+                i-= s->header_size -1;
+                s->remaining_size = len;
+                if(!new_frame_start){
+                    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;
+    /* allow downmixing to stereo (or mono for AC3) */
+    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->channels = avctx->request_channels;
+    } else {
+        avctx->channels = s->channels;
+    }
+    avctx->bit_rate = s->bit_rate;
+    avctx->frame_size = s->samples;
+
+    return i;
 }