| Message ID | 20211019210244.4130-1-jeffm@jeffm.io |
|---|---|
| State | New |
| Headers | show |
| Series | [FFmpeg-devel,v2] libavformat/rtpdec_mpeg: handle bare ADTS packets with explicit decoder config | expand |
| Context | Check | Description |
|---|---|---|
| andriy/make_x86 | success | Make finished |
| andriy/make_fate_x86 | success | Make fate finished |
| andriy/make_ppc | success | Make finished |
| andriy/make_fate_ppc | success | Make fate finished |
On Tue, Oct 19, 2021 at 05:02:44PM -0400, Jeff Mahoney wrote: The title should be "avformat/rtpdec_mpeg4: ..." > When SDP specifies a decoder config, there may not be any AU headers > provided by the sender. This can result in rtp_parse_mp4_au failing > and aac_parse_packet reporting "Error parsing AU headers." and no audio > is recovered from the stream. > > This commit modifies aac_parse_header to check for an explicit decoder config > set by the sdp parser (e.g. a:fmtp # config=hexvalue). If it has and there > is an ADTS header present, it skips the header and copies the RTP > payload directly as an AAC packet. > > This resolves an issue observed with some inexpensive IP cameras. How to test the issue without such IP cameras? > > Signed-off-by: Jeff Mahoney <jeffm@jeffm.io> > --- > libavformat/rtpdec_mpeg4.c | 37 ++++++++++++++++++++++++++++++++++++- > 1 file changed, 36 insertions(+), 1 deletion(-) > > diff --git a/libavformat/rtpdec_mpeg4.c b/libavformat/rtpdec_mpeg4.c > index 34c7950bcc..13d0770dd6 100644 > --- a/libavformat/rtpdec_mpeg4.c > +++ b/libavformat/rtpdec_mpeg4.c > @@ -32,6 +32,8 @@ > #include "libavutil/attributes.h" > #include "libavutil/avstring.h" > #include "libavcodec/get_bits.h" > +#include "libavcodec/adts_header.h" > +#include "libavcodec/adts_parser.h" > > #define MAX_AAC_HBR_FRAME_SIZE 8191 > > @@ -176,7 +178,7 @@ static int aac_parse_packet(AVFormatContext *ctx, PayloadContext *data, > int flags) > { > int ret; > - > + AVCodecParameters *par = st->codecpar; > > if (!buf) { > if (data->cur_au_index > data->nb_au_headers) { > @@ -204,6 +206,39 @@ static int aac_parse_packet(AVFormatContext *ctx, PayloadContext *data, > return 1; > } > > + /* Check for an explicit decoder config (e.g. SDP a:fmtp... config=) */ > + if (par->extradata && len > 7) { 7 is better to use AV_AAC_ADTS_HEADER_SIZE like the following. > + AACADTSHeaderInfo *header; > + > + /* > + * Check for ADTS header > + * If present skip the header and copy the entire payload as AAC data > + */ > + ret = avpriv_adts_header_parse(&header, buf, len); need add adts_header dependency for rtp demuer. > + if (!ret) { > + buf += AV_AAC_ADTS_HEADER_SIZE; > + len -= AV_AAC_ADTS_HEADER_SIZE; > + > + /* Skip 16-bit CRC if present */ > + if (!header->crc_absent) { > + buf += 2; > + len -= 2; > + } > + av_free(header); > + > + ret = av_new_packet(pkt, len); > + if (ret < 0) { > + av_log(ctx, AV_LOG_ERROR, "Out of memory\n"); > + return ret; > + } > + > + memcpy(pkt->data, buf, len); > + pkt->stream_index = st->index; > + > + return 0; > + } > + } > + > if (rtp_parse_mp4_au(data, buf, len)) { > av_log(ctx, AV_LOG_ERROR, "Error parsing AU headers\n"); > return -1; > -- > 2.33.1 > > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > https://ffmpeg.org/mailman/listinfo/ffmpeg-devel > > To unsubscribe, visit link above, or email > ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".
diff --git a/libavformat/rtpdec_mpeg4.c b/libavformat/rtpdec_mpeg4.c index 34c7950bcc..13d0770dd6 100644 --- a/libavformat/rtpdec_mpeg4.c +++ b/libavformat/rtpdec_mpeg4.c @@ -32,6 +32,8 @@ #include "libavutil/attributes.h" #include "libavutil/avstring.h" #include "libavcodec/get_bits.h" +#include "libavcodec/adts_header.h" +#include "libavcodec/adts_parser.h" #define MAX_AAC_HBR_FRAME_SIZE 8191 @@ -176,7 +178,7 @@ static int aac_parse_packet(AVFormatContext *ctx, PayloadContext *data, int flags) { int ret; - + AVCodecParameters *par = st->codecpar; if (!buf) { if (data->cur_au_index > data->nb_au_headers) { @@ -204,6 +206,39 @@ static int aac_parse_packet(AVFormatContext *ctx, PayloadContext *data, return 1; } + /* Check for an explicit decoder config (e.g. SDP a:fmtp... config=) */ + if (par->extradata && len > 7) { + AACADTSHeaderInfo *header; + + /* + * Check for ADTS header + * If present skip the header and copy the entire payload as AAC data + */ + ret = avpriv_adts_header_parse(&header, buf, len); + if (!ret) { + buf += AV_AAC_ADTS_HEADER_SIZE; + len -= AV_AAC_ADTS_HEADER_SIZE; + + /* Skip 16-bit CRC if present */ + if (!header->crc_absent) { + buf += 2; + len -= 2; + } + av_free(header); + + ret = av_new_packet(pkt, len); + if (ret < 0) { + av_log(ctx, AV_LOG_ERROR, "Out of memory\n"); + return ret; + } + + memcpy(pkt->data, buf, len); + pkt->stream_index = st->index; + + return 0; + } + } + if (rtp_parse_mp4_au(data, buf, len)) { av_log(ctx, AV_LOG_ERROR, "Error parsing AU headers\n"); return -1;
When SDP specifies a decoder config, there may not be any AU headers provided by the sender. This can result in rtp_parse_mp4_au failing and aac_parse_packet reporting "Error parsing AU headers." and no audio is recovered from the stream. This commit modifies aac_parse_header to check for an explicit decoder config set by the sdp parser (e.g. a:fmtp # config=hexvalue). If it has and there is an ADTS header present, it skips the header and copies the RTP payload directly as an AAC packet. This resolves an issue observed with some inexpensive IP cameras. Signed-off-by: Jeff Mahoney <jeffm@jeffm.io> --- libavformat/rtpdec_mpeg4.c | 37 ++++++++++++++++++++++++++++++++++++- 1 file changed, 36 insertions(+), 1 deletion(-)