From 454064ad1eb39ffbea4906dbe2e246e18a5d5d67 Mon Sep 17 00:00:00 2001
From: Michael Niedermayer <michaelni@gmx.at>
Date: Sat, 19 Apr 2008 01:50:40 +0000
Subject: [PATCH] Change aac and ac3 parsers to use ff_combine_frame().

Originally committed as revision 12894 to svn://svn.ffmpeg.org/ffmpeg/trunk
---
 libavcodec/aac_ac3_parser.c | 69 +++++++++++++++++++++------------------------
 libavcodec/aac_ac3_parser.h |  8 ++++--
 libavcodec/aac_parser.c     |  6 ++--
 libavcodec/ac3_parser.c     |  6 ++--
 4 files changed, 43 insertions(+), 46 deletions(-)

diff --git a/libavcodec/aac_ac3_parser.c b/libavcodec/aac_ac3_parser.c
index c72965a..b3d4556 100644
--- a/libavcodec/aac_ac3_parser.c
+++ b/libavcodec/aac_ac3_parser.c
@@ -29,34 +29,40 @@ 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;
+    ParseContext *pc = &s->pc;
+    int len, i;
 
-    *poutbuf = NULL;
-    *poutbuf_size = 0;
+    i=END_NOT_FOUND;
+    if(s->remaining_size <= buf_size){
+        if(s->remaining_size){
+            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)))
+                    break;
+            }
+            if(len<=0){
+                i=END_NOT_FOUND;
+            }else{
+                i-= s->header_size -1;
+                s->remaining_size = len + i;
+            }
+        }
+    }
 
-    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(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;
+    }
 
-        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;
-        }
+    *poutbuf = buf;
+    *poutbuf_size = buf_size;
 
-        if (s->frame_size == 0) {
-            if ((s->inbuf_ptr - s->inbuf) == s->header_size) {
-                len = s->sync(s);
-                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 = s->sample_rate;
                     /* allow downmixing to stereo (or mono for AC3) */
@@ -71,17 +77,6 @@ int ff_aac_ac3_parse(AVCodecParserContext *s1,
                     }
                     avctx->bit_rate = s->bit_rate;
                     avctx->frame_size = s->samples;
-                }
-            }
-        } 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;
-            }
-        }
-    }
-    return buf_ptr - buf;
+
+    return i;
 }
diff --git a/libavcodec/aac_ac3_parser.h b/libavcodec/aac_ac3_parser.h
index f93f8a8..cb84b8d 100644
--- a/libavcodec/aac_ac3_parser.h
+++ b/libavcodec/aac_ac3_parser.h
@@ -27,16 +27,18 @@
 #include "avcodec.h"
 
 typedef struct AACAC3ParseContext {
-    uint8_t *inbuf_ptr;
     int frame_size;
     int header_size;
-    int (*sync)(struct AACAC3ParseContext *hdr_info);
-    uint8_t inbuf[8192]; /* input buffer */
+    int (*sync)(uint64_t state, struct AACAC3ParseContext *hdr_info);
 
     int channels;
     int sample_rate;
     int bit_rate;
     int samples;
+
+    ParseContext pc;
+    int remaining_size;
+    uint64_t state;
 } AACAC3ParseContext;
 
 int ff_aac_ac3_parse(AVCodecParserContext *s1,
diff --git a/libavcodec/aac_parser.c b/libavcodec/aac_parser.c
index 8715ce6..a2e95f7 100644
--- a/libavcodec/aac_parser.c
+++ b/libavcodec/aac_parser.c
@@ -27,12 +27,13 @@
 
 #define AAC_HEADER_SIZE 7
 
-static int aac_sync(AACAC3ParseContext *hdr_info)
+static int aac_sync(uint64_t state, AACAC3ParseContext *hdr_info)
 {
     GetBitContext bits;
     int size, rdb, ch, sr;
+    uint64_t tmp = be2me_64(state);
 
-    init_get_bits(&bits, hdr_info->inbuf, AAC_HEADER_SIZE * 8);
+    init_get_bits(&bits, ((uint8_t *)&tmp)+8-AAC_HEADER_SIZE, AAC_HEADER_SIZE * 8);
 
     if(get_bits(&bits, 12) != 0xfff)
         return 0;
@@ -72,7 +73,6 @@ static int aac_sync(AACAC3ParseContext *hdr_info)
 static av_cold int aac_parse_init(AVCodecParserContext *s1)
 {
     AACAC3ParseContext *s = s1->priv_data;
-    s->inbuf_ptr = s->inbuf;
     s->header_size = AAC_HEADER_SIZE;
     s->sync = aac_sync;
     return 0;
diff --git a/libavcodec/ac3_parser.c b/libavcodec/ac3_parser.c
index bc728c1..5112233 100644
--- a/libavcodec/ac3_parser.c
+++ b/libavcodec/ac3_parser.c
@@ -123,12 +123,13 @@ int ff_ac3_parse_header(const uint8_t buf[7], AC3HeaderInfo *hdr)
     return 0;
 }
 
-static int ac3_sync(AACAC3ParseContext *hdr_info)
+static int ac3_sync(uint64_t state, AACAC3ParseContext *hdr_info)
 {
     int err;
+    uint64_t tmp = be2me_64(state);
     AC3HeaderInfo hdr;
 
-    err = ff_ac3_parse_header(hdr_info->inbuf, &hdr);
+    err = ff_ac3_parse_header(((uint8_t *)&tmp)+8-AC3_HEADER_SIZE, &hdr);
 
     if(err < 0)
         return 0;
@@ -144,7 +145,6 @@ static int ac3_sync(AACAC3ParseContext *hdr_info)
 static av_cold int ac3_parse_init(AVCodecParserContext *s1)
 {
     AACAC3ParseContext *s = s1->priv_data;
-    s->inbuf_ptr = s->inbuf;
     s->header_size = AC3_HEADER_SIZE;
     s->sync = ac3_sync;
     return 0;
-- 
2.7.4