[FFmpeg-devel] [PATCH] avformat/movenc: add EAC3 muxing support.
Benoit Fouet
benoit.fouet at free.fr
Tue Oct 7 15:02:38 CEST 2014
Support only one independent substream right now, and only syncframes
containing 6 blocks.
Fixes part of ticket #3074
---
Right now, this produces the same output as the previous patch for supported
streams, and rejects the unsupported ones.
Support for syncframes concatenation will come afterwards.
libavformat/isom.c | 1 +
libavformat/movenc.c | 184 +++++++++++++++++++++++++++++++++++++++++++++++++++
libavformat/movenc.h | 2 +
3 files changed, 187 insertions(+)
diff --git a/libavformat/isom.c b/libavformat/isom.c
index d768c32..1509021 100644
--- a/libavformat/isom.c
+++ b/libavformat/isom.c
@@ -57,6 +57,7 @@ const AVCodecTag ff_mp4_obj_type[] = {
{ AV_CODEC_ID_VC1 , 0xA3 },
{ AV_CODEC_ID_DIRAC , 0xA4 },
{ AV_CODEC_ID_AC3 , 0xA5 },
+ { AV_CODEC_ID_EAC3 , 0xA6 },
{ AV_CODEC_ID_DTS , 0xA9 }, /* mp4ra.org */
{ AV_CODEC_ID_VORBIS , 0xDD }, /* non standard, gpac uses it */
{ AV_CODEC_ID_DVD_SUBTITLE, 0xE0 }, /* non standard, see unsupported-embedded-subs-2.mp4 */
diff --git a/libavformat/movenc.c b/libavformat/movenc.c
index bfee866..18c5955 100644
--- a/libavformat/movenc.c
+++ b/libavformat/movenc.c
@@ -31,6 +31,7 @@
#include "avio.h"
#include "isom.h"
#include "avc.h"
+#include "libavcodec/ac3_parser.h"
#include "libavcodec/get_bits.h"
#include "libavcodec/put_bits.h"
#include "libavcodec/vc1_common.h"
@@ -292,6 +293,178 @@ static int mov_write_ac3_tag(AVIOContext *pb, MOVTrack *track)
return 11;
}
+struct eac3_info {
+ uint8_t ec3_done;
+
+ /* Layout of the EC3SpecificBox */
+ /* maximum bitrate */
+ uint16_t data_rate;
+ /* number of independent substreams */
+ uint8_t num_ind_sub;
+ struct {
+ /* sample rate code (see ff_ac3_sample_rate_tab) 2 bits */
+ uint8_t fscod;
+ /* bit stream identification 5 bits */
+ uint8_t bsid;
+ /* one bit reserved */
+ /* audio service mixing (not supported yet) 1 bit */
+ /* bit stream mode 3 bits */
+ uint8_t bsmod;
+ /* audio coding mode 3 bits */
+ uint8_t acmod;
+ /* sub woofer on 1 bit */
+ uint8_t lfeon;
+ /* 3 bits reserved */
+ /* number of dependent substreams associated with this substream 4 bits */
+ uint8_t num_dep_sub;
+ /* channel locations of the dependent substream(s), if any, 9 bits */
+ uint16_t chan_loc;
+ /* if there is no dependent substream, then one bit reserved instead */
+ } substream[1]; /* TODO: support 8 independent substreams */
+};
+
+static int handle_eac3(AVPacket *pkt, MOVTrack *track)
+{
+ GetBitContext gbc;
+ AC3HeaderInfo tmp, *hdr = &tmp;
+ struct eac3_info *info;
+ int ret, num_blocks;
+
+ if (!track->eac3_priv && !(track->eac3_priv = av_mallocz(sizeof(*info))))
+ return AVERROR(ENOMEM);
+ info = track->eac3_priv;
+
+ init_get_bits(&gbc, pkt->data, pkt->size * 8);
+ if ((ret = avpriv_ac3_parse_header2(&gbc, &hdr)) < 0)
+ return ret;
+
+ info->data_rate = FFMAX(info->data_rate, hdr->bit_rate);
+ num_blocks = hdr->num_blocks;
+
+ if (!info->ec3_done) {
+ /* AC-3 substream must be the first one */
+ if (hdr->bitstream_id <= 10 && hdr->substreamid != 0)
+ return AVERROR(EINVAL);
+
+ /* this should always be the case, given that our AC-3 parser
+ * concatenates dependent frames to their independent parent */
+ if (hdr->frame_type == EAC3_FRAME_TYPE_INDEPENDENT) {
+ /* substream ids must be incremental */
+ if (hdr->substreamid > info->num_ind_sub + 1)
+ return AVERROR(EINVAL);
+
+ if (hdr->substreamid == info->num_ind_sub + 1) {
+ //info->num_ind_sub++;
+ avpriv_request_sample(track->enc, "Multiple independent substreams");
+ return AVERROR_PATCHWELCOME;
+ } else if (hdr->substreamid < info->num_ind_sub ||
+ hdr->substreamid == 0 && info->substream[0].bsid) {
+ info->ec3_done = 1;
+ goto concatenate;
+ }
+ }
+
+ /* fill the info needed for the "dec3" atom */
+ info->substream[hdr->substreamid].fscod = hdr->sr_code;
+ info->substream[hdr->substreamid].bsid = hdr->bitstream_id;
+ info->substream[hdr->substreamid].bsmod = hdr->bitstream_mode;
+ info->substream[hdr->substreamid].acmod = hdr->channel_mode;
+ info->substream[hdr->substreamid].lfeon = hdr->lfe_on;
+
+ /* Parse dependent substream(s), if any */
+ if (pkt->size != hdr->frame_size) {
+ int cumul_size = hdr->frame_size;
+ int parent = hdr->substreamid;
+
+ while (cumul_size != pkt->size) {
+ int i;
+ init_get_bits(&gbc, pkt->data + cumul_size, (pkt->size - cumul_size) * 8);
+ if ((ret = avpriv_ac3_parse_header2(&gbc, &hdr)) < 0)
+ return ret;
+ if (hdr->frame_type != EAC3_FRAME_TYPE_DEPENDENT)
+ return AVERROR(EINVAL);
+ cumul_size += hdr->frame_size;
+ info->substream[parent].num_dep_sub++;
+
+ /* header is parsed up to lfeon, but custom channel map may be needed */
+ /* skip bsid */
+ skip_bits(&gbc, 5);
+ /* skip volume control params */
+ for (i = 0; i < (hdr->channel_mode ? 1 : 2); i++) {
+ skip_bits(&gbc, 5); // skip dialog normalization
+ if (get_bits1(&gbc)) {
+ skip_bits(&gbc, 8); // skip compression gain word
+ }
+ }
+ /* get the dependent stream channel map, if exists */
+ if (get_bits1(&gbc))
+ info->substream[parent].chan_loc |= (get_bits(&gbc, 16) >> 5) & 0x1f;
+ else
+ info->substream[parent].chan_loc |= hdr->channel_mode;
+ }
+ }
+ }
+
+/* TODO: concatenate syncframes to have 6 blocks per entry */
+concatenate:
+ if (num_blocks != 6) {
+ avpriv_request_sample(track->enc, "%d block(s) in syncframe", num_blocks);
+ return AVERROR_PATCHWELCOME;
+ }
+
+ return pkt->size;
+}
+
+static int mov_write_eac3_tag(AVIOContext *pb, MOVTrack *track)
+{
+ PutBitContext pbc;
+ uint8_t *buf;
+ struct eac3_info *info;
+ int size, i;
+
+ if (!track->eac3_priv)
+ return AVERROR(EINVAL);
+
+ info = track->eac3_priv;
+ size = 2 + 4 * (info->num_ind_sub + 1);
+ buf = av_malloc(size);
+ if (!buf) {
+ av_freep(&track->eac3_priv);
+ return AVERROR(ENOMEM);
+ }
+
+ init_put_bits(&pbc, buf, size);
+ put_bits(&pbc, 13, info->data_rate);
+ put_bits(&pbc, 3, info->num_ind_sub);
+ for (i = 0; i <= info->num_ind_sub; i++) {
+ put_bits(&pbc, 2, info->substream[i].fscod);
+ put_bits(&pbc, 5, info->substream[i].bsid);
+ put_bits(&pbc, 1, 0); /* reserved */
+ put_bits(&pbc, 1, 0); /* asvc */
+ put_bits(&pbc, 3, info->substream[i].bsmod);
+ put_bits(&pbc, 3, info->substream[i].acmod);
+ put_bits(&pbc, 1, info->substream[i].lfeon);
+ put_bits(&pbc, 5, 0); /* reserved */
+ put_bits(&pbc, 4, info->substream[i].num_dep_sub);
+ if (!info->substream[i].num_dep_sub) {
+ put_bits(&pbc, 1, 0); /* reserved */
+ size--;
+ } else {
+ put_bits(&pbc, 9, info->substream[i].chan_loc);
+ }
+ }
+ flush_put_bits(&pbc);
+
+ avio_wb32(pb, size + 8);
+ ffio_wfourcc(pb, "dec3");
+ avio_write(pb, buf, size);
+
+ av_free(buf);
+ av_freep(&track->eac3_priv);
+
+ return size;
+}
+
/**
* This function writes extradata "as is".
* Extradata must be formatted like a valid atom (with size and tag).
@@ -486,6 +659,8 @@ static int mov_write_wave_tag(AVIOContext *pb, MOVTrack *track)
mov_write_amr_tag(pb, track);
} else if (track->enc->codec_id == AV_CODEC_ID_AC3) {
mov_write_ac3_tag(pb, track);
+ } else if (track->enc->codec_id == AV_CODEC_ID_EAC3) {
+ mov_write_eac3_tag(pb, track);
} else if (track->enc->codec_id == AV_CODEC_ID_ALAC ||
track->enc->codec_id == AV_CODEC_ID_QDM2) {
mov_write_extradata_tag(pb, track);
@@ -756,6 +931,7 @@ static int mov_write_audio_tag(AVIOContext *pb, MOVTrack *track)
if (track->mode == MODE_MOV &&
(track->enc->codec_id == AV_CODEC_ID_AAC ||
track->enc->codec_id == AV_CODEC_ID_AC3 ||
+ track->enc->codec_id == AV_CODEC_ID_EAC3 ||
track->enc->codec_id == AV_CODEC_ID_AMR_NB ||
track->enc->codec_id == AV_CODEC_ID_ALAC ||
track->enc->codec_id == AV_CODEC_ID_ADPCM_MS ||
@@ -770,6 +946,8 @@ static int mov_write_audio_tag(AVIOContext *pb, MOVTrack *track)
mov_write_amr_tag(pb, track);
else if (track->enc->codec_id == AV_CODEC_ID_AC3)
mov_write_ac3_tag(pb, track);
+ else if (track->enc->codec_id == AV_CODEC_ID_EAC3)
+ mov_write_eac3_tag(pb, track);
else if (track->enc->codec_id == AV_CODEC_ID_ALAC)
mov_write_extradata_tag(pb, track);
else if (track->enc->codec_id == AV_CODEC_ID_WMAPRO)
@@ -877,6 +1055,7 @@ static int mp4_get_codec_tag(AVFormatContext *s, MOVTrack *track)
if (track->enc->codec_id == AV_CODEC_ID_H264) tag = MKTAG('a','v','c','1');
else if (track->enc->codec_id == AV_CODEC_ID_HEVC) tag = MKTAG('h','e','v','1');
else if (track->enc->codec_id == AV_CODEC_ID_AC3) tag = MKTAG('a','c','-','3');
+ else if (track->enc->codec_id == AV_CODEC_ID_EAC3) tag = MKTAG('e','c','-','3');
else if (track->enc->codec_id == AV_CODEC_ID_DIRAC) tag = MKTAG('d','r','a','c');
else if (track->enc->codec_id == AV_CODEC_ID_MOV_TEXT) tag = MKTAG('t','x','3','g');
else if (track->enc->codec_id == AV_CODEC_ID_VC1) tag = MKTAG('v','c','-','1');
@@ -3600,6 +3779,11 @@ int ff_mov_write_packet(AVFormatContext *s, AVPacket *pkt)
} else {
size = ff_hevc_annexb2mp4(pb, pkt->data, pkt->size, 0, NULL);
}
+ } else if (enc->codec_id == AV_CODEC_ID_EAC3) {
+ size = handle_eac3(pkt, trk);
+ if (size < 0)
+ return size;
+ avio_write(pb, pkt->data, size);
} else {
avio_write(pb, pkt->data, size);
}
diff --git a/libavformat/movenc.h b/libavformat/movenc.h
index 9ce4a86..4e7db7a 100644
--- a/libavformat/movenc.h
+++ b/libavformat/movenc.h
@@ -142,6 +142,8 @@ typedef struct MOVTrack {
int packet_entry;
int slices;
} vc1_info;
+
+ void *eac3_priv;
} MOVTrack;
typedef struct MOVMuxContext {
--
2.1.0.127.g0c72b98
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