[FFmpeg-cvslog] avcodec/aac_ac3_parser: don't fill stream info in the sync function

James Almer git at videolan.org
Wed Oct 26 16:33:57 EEST 2022


ffmpeg | branch: master | James Almer <jamrial at gmail.com> | Sat Oct 22 16:30:52 2022 -0300| [b5abf6fdfc0d1bd8b009f8877589f1bc7eec3e9c] | committer: James Almer

avcodec/aac_ac3_parser: don't fill stream info in the sync function

Have it only find frame boundaries. The stream props will then be filled once
we have an assembled frame.

Signed-off-by: James Almer <jamrial at gmail.com>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=b5abf6fdfc0d1bd8b009f8877589f1bc7eec3e9c
---

 libavcodec/aac_ac3_parser.c | 63 +++++++++++++++++++++++++++++++++++----------
 libavcodec/aac_ac3_parser.h | 12 +--------
 libavcodec/aac_parser.c     |  7 +----
 libavcodec/ac3_parser.c     | 16 +-----------
 4 files changed, 53 insertions(+), 45 deletions(-)

diff --git a/libavcodec/aac_ac3_parser.c b/libavcodec/aac_ac3_parser.c
index b14b1e31f9..6df064e28d 100644
--- a/libavcodec/aac_ac3_parser.c
+++ b/libavcodec/aac_ac3_parser.c
@@ -26,6 +26,8 @@
 #include "libavutil/common.h"
 #include "parser.h"
 #include "aac_ac3_parser.h"
+#include "ac3_parser_internal.h"
+#include "adts_header.h"
 
 int ff_aac_ac3_parse(AVCodecParserContext *s1,
                      AVCodecContext *avctx,
@@ -48,7 +50,7 @@ get_next:
             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)))
+                if((len=s->sync(s->state, &s->need_next_header, &new_frame_start)))
                     break;
             }
             if(len<=0){
@@ -79,42 +81,77 @@ get_next:
     *poutbuf = buf;
     *poutbuf_size = buf_size;
 
-    /* update codec info */
-    if(s->codec_id)
-        avctx->codec_id = s->codec_id;
-
     if (got_frame) {
+        int bit_rate;
+
         /* Due to backwards compatible HE-AAC the sample rate, channel count,
            and total number of samples found in an AAC ADTS header are not
            reliable. Bit rate is still accurate because the total frame
            duration in seconds is still correct (as is the number of bits in
            the frame). */
         if (avctx->codec_id != AV_CODEC_ID_AAC) {
-            avctx->sample_rate = s->sample_rate;
+            AC3HeaderInfo hdr, *phrd = &hdr;
+            int offset = ff_ac3_find_syncword(buf, buf_size);
+
+            if (offset < 0)
+                return i;
+
+            buf += offset;
+            buf_size -= offset;
+            while (buf_size > 0) {
+                int ret = avpriv_ac3_parse_header(&phrd, buf, buf_size);
+
+                if (ret < 0 || hdr.frame_size > buf_size)
+                    return i;
+
+                if (buf_size > hdr.frame_size) {
+                    buf += hdr.frame_size;
+                    buf_size -= hdr.frame_size;
+                    continue;
+                }
+                break;
+            }
+
+            avctx->sample_rate = hdr.sample_rate;
+
+            if (hdr.bitstream_id > 10)
+                avctx->codec_id = AV_CODEC_ID_EAC3;
+
             if (!CONFIG_EAC3_DECODER || avctx->codec_id != AV_CODEC_ID_EAC3) {
                 av_channel_layout_uninit(&avctx->ch_layout);
-                if (s->channel_layout) {
-                    av_channel_layout_from_mask(&avctx->ch_layout, s->channel_layout);
+                if (hdr.channel_layout) {
+                    av_channel_layout_from_mask(&avctx->ch_layout, hdr.channel_layout);
                 } else {
                     avctx->ch_layout.order       = AV_CHANNEL_ORDER_UNSPEC;
-                    avctx->ch_layout.nb_channels = s->channels;
+                    avctx->ch_layout.nb_channels = hdr.channels;
                 }
 #if FF_API_OLD_CHANNEL_LAYOUT
 FF_DISABLE_DEPRECATION_WARNINGS
                 avctx->channels = avctx->ch_layout.nb_channels;
-                avctx->channel_layout = s->channel_layout;
+                avctx->channel_layout = hdr.channel_layout;
 FF_ENABLE_DEPRECATION_WARNINGS
 #endif
             }
-            s1->duration = s->samples;
-            avctx->audio_service_type = s->service_type;
+            s1->duration = hdr.num_blocks * 256;
+            avctx->audio_service_type = hdr.bitstream_mode;
+            if (hdr.bitstream_mode == 0x7 && hdr.channels > 1)
+                avctx->audio_service_type = AV_AUDIO_SERVICE_TYPE_KARAOKE;
+            bit_rate = hdr.bit_rate;
+        } else {
+            AACADTSHeaderInfo hdr, *phrd = &hdr;
+            int ret = avpriv_adts_header_parse(&phrd, buf, buf_size);
+
+            if (ret < 0)
+                return i;
+
+            bit_rate = hdr.bit_rate;
         }
 
         /* Calculate the average bit rate */
         s->frame_number++;
         if (!CONFIG_EAC3_DECODER || avctx->codec_id != AV_CODEC_ID_EAC3) {
             avctx->bit_rate +=
-                (s->bit_rate - avctx->bit_rate) / s->frame_number;
+                (bit_rate - avctx->bit_rate) / s->frame_number;
         }
     }
 
diff --git a/libavcodec/aac_ac3_parser.h b/libavcodec/aac_ac3_parser.h
index 8b93cbf84f..560bba54f5 100644
--- a/libavcodec/aac_ac3_parser.h
+++ b/libavcodec/aac_ac3_parser.h
@@ -39,24 +39,14 @@ typedef enum {
 
 typedef struct AACAC3ParseContext {
     ParseContext pc;
-    int frame_size;
     int header_size;
-    int (*sync)(uint64_t state, struct AACAC3ParseContext *hdr_info,
-            int *need_next_header, int *new_frame_start);
-
-    int channels;
-    int sample_rate;
-    int bit_rate;
-    int samples;
-    uint64_t channel_layout;
-    int service_type;
+    int (*sync)(uint64_t state, int *need_next_header, int *new_frame_start);
 
     int remaining_size;
     uint64_t state;
 
     int need_next_header;
     int frame_number;
-    enum AVCodecID codec_id;
 } AACAC3ParseContext;
 
 int ff_aac_ac3_parse(AVCodecParserContext *s1,
diff --git a/libavcodec/aac_parser.c b/libavcodec/aac_parser.c
index f3baf7cde3..f295dfccdd 100644
--- a/libavcodec/aac_parser.c
+++ b/libavcodec/aac_parser.c
@@ -27,8 +27,7 @@
 #include "get_bits.h"
 #include "mpeg4audio.h"
 
-static int aac_sync(uint64_t state, AACAC3ParseContext *hdr_info,
-        int *need_next_header, int *new_frame_start)
+static int aac_sync(uint64_t state, int *need_next_header, int *new_frame_start)
 {
     GetBitContext bits;
     AACADTSHeaderInfo hdr;
@@ -46,10 +45,6 @@ static int aac_sync(uint64_t state, AACAC3ParseContext *hdr_info,
         return 0;
     *need_next_header = 0;
     *new_frame_start  = 1;
-    hdr_info->sample_rate = hdr.sample_rate;
-    hdr_info->channels    = ff_mpeg4audio_channels[hdr.chan_config];
-    hdr_info->samples     = hdr.samples;
-    hdr_info->bit_rate    = hdr.bit_rate;
     return size;
 }
 
diff --git a/libavcodec/ac3_parser.c b/libavcodec/ac3_parser.c
index 425e1b4742..8885e1c72e 100644
--- a/libavcodec/ac3_parser.c
+++ b/libavcodec/ac3_parser.c
@@ -215,8 +215,7 @@ int av_ac3_parse_header(const uint8_t *buf, size_t size,
     return 0;
 }
 
-static int ac3_sync(uint64_t state, AACAC3ParseContext *hdr_info,
-        int *need_next_header, int *new_frame_start)
+static int ac3_sync(uint64_t state, int *need_next_header, int *new_frame_start)
 {
     int err;
     union {
@@ -238,19 +237,6 @@ static int ac3_sync(uint64_t state, AACAC3ParseContext *hdr_info,
     if(err < 0)
         return 0;
 
-    hdr_info->sample_rate = hdr.sample_rate;
-    hdr_info->bit_rate = hdr.bit_rate;
-    hdr_info->channels = hdr.channels;
-    hdr_info->channel_layout = hdr.channel_layout;
-    hdr_info->samples = hdr.num_blocks * 256;
-    hdr_info->service_type = hdr.bitstream_mode;
-    if (hdr.bitstream_mode == 0x7 && hdr.channels > 1)
-        hdr_info->service_type = AV_AUDIO_SERVICE_TYPE_KARAOKE;
-    if(hdr.bitstream_id>10)
-        hdr_info->codec_id = AV_CODEC_ID_EAC3;
-    else if (hdr_info->codec_id == AV_CODEC_ID_NONE)
-        hdr_info->codec_id = AV_CODEC_ID_AC3;
-
     *new_frame_start  = (hdr.frame_type != EAC3_FRAME_TYPE_DEPENDENT);
     *need_next_header = *new_frame_start || (hdr.frame_type != EAC3_FRAME_TYPE_AC3_CONVERT);
     return hdr.frame_size;



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