On 26.02.2015 15:41, Michael Niedermayer wrote:
On Thu, Feb 26, 2015 at 02:14:33PM +0100, Tobias Rapp wrote:
On 26.02.2015 00:51, Michael Niedermayer wrote:
On Wed, Feb 25, 2015 at 05:35:33PM +0100, Tobias Rapp wrote:
[...]
@@ -511,7 +514,11 @@ static int avi_write_ix(AVFormatContext *s)
avio_skip(pb, 16 * avi->riff_id);
avio_wl64(pb, ix); /* qwOffset */
avio_wl32(pb, pos - ix); /* dwSize */
- avio_wl32(pb, avist->indexes.entry); /* dwDuration */
+ ff_parse_specific_params(s->streams[i], &au_byterate, &au_ssize,
&au_scale);
+ if (au_ssize == 0)
+ avio_wl32(pb, avist->indexes.entry); /* dwDuration (packet count)
*/
+ else
+ avio_wl32(pb, (avist->audio_strm_length -
avist->indexes.audio_strm_offset) / au_ssize); /* dwDuration (sample count) */
the rounding here is wrong
the index to be useable needs to have segments duration summable
as is this would lead to significangt errors if many of these
durations would be summed up
something like
avist->audio_strm_length / au_ssize - avist->indexes.audio_strm_offset /
au_ssize
might avoid that but ive not tested it
My assumption was that a stream packet contains only whole samples
for linear/uncompressed audio (PCM) and that only for linear audio
the expression "au_ssize > 0" evaluates to TRUE.
We try to use au_ssize = 0 for compressed audio but i think it can be
non zero in some stream copy cases, iam not 100% sure though
If that is not the case I can do the rounding as suggested or maybe
introduce some separate stream duration counter based on
AVPacket.duration?
i think best to keep it simple and maybe print a request for a sample/
testcase if some combination of parameters is found which we are
unsure about if it works correctly
Attached a new patch that calls avpriv_request_sample if the audio
segment size is no multiple of au_ssize. Tested different audio encoder
types (pcm_s16le, pcm_s24le, adpcm_ms, mp2, libmp3lame) with success.
Regards,
Tobias
>From 89d3f13169e2ff183a1e60c9939263035ad83a0f Mon Sep 17 00:00:00 2001
From: Tobias Rapp <t.r...@noa-audio.com>
Date: Tue, 3 Mar 2015 13:29:05 +0100
Subject: [PATCH] libavformat/avienc: Fix duration of audio segment in OpenDML
master index
Fixes the duration field of the OpenDML master index "indx" chunk to
contain the number of samples instead of the number of packets for
(linear/PCM) audio streams.
This matches the OpenDML V1.02 standard text which states that the
duration field shall contain "time span in stream ticks".
---
libavformat/avienc.c | 15 ++++++++++++++-
1 file changed, 14 insertions(+), 1 deletion(-)
diff --git a/libavformat/avienc.c b/libavformat/avienc.c
index 53c2fe7..3b5e5c4 100644
--- a/libavformat/avienc.c
+++ b/libavformat/avienc.c
@@ -49,6 +49,7 @@ typedef struct AVIIentry {
typedef struct AVIIndex {
int64_t indx_start;
+ int64_t audio_strm_offset;
int entry;
int ents_allocated;
AVIIentry** cluster;
@@ -66,6 +67,7 @@ typedef struct AVIStream {
int packet_count;
int entry;
int max_size;
+ int sample_requested;
int64_t last_dts;
@@ -91,6 +93,7 @@ static int64_t avi_start_new_riff(AVFormatContext *s,
AVIOContext *pb,
avi->riff_id++;
for (i = 0; i < s->nb_streams; i++) {
AVIStream *avist = s->streams[i]->priv_data;
+ avist->indexes.audio_strm_offset = avist->audio_strm_length;
avist->indexes.entry = 0;
}
@@ -476,6 +479,7 @@ static int avi_write_ix(AVFormatContext *s)
for (i = 0; i < s->nb_streams; i++) {
AVIStream *avist = s->streams[i]->priv_data;
int64_t ix, pos;
+ int au_byterate, au_ssize, au_scale;
avi_stream2fourcc(tag, i, s->streams[i]->codec->codec_type);
ix_tag[3] = '0' + i;
@@ -511,7 +515,16 @@ static int avi_write_ix(AVFormatContext *s)
avio_skip(pb, 16 * avi->riff_id);
avio_wl64(pb, ix); /* qwOffset */
avio_wl32(pb, pos - ix); /* dwSize */
- avio_wl32(pb, avist->indexes.entry); /* dwDuration */
+ ff_parse_specific_params(s->streams[i], &au_byterate, &au_ssize,
&au_scale);
+ if (s->streams[i]->codec->codec_type == AVMEDIA_TYPE_AUDIO && au_ssize
> 0) {
+ uint32_t audio_segm_size = (avist->audio_strm_length -
avist->indexes.audio_strm_offset);
+ if ((audio_segm_size % au_ssize > 0) && !avist->sample_requested) {
+ avpriv_request_sample(s, "OpenDML index duration for audio
packets with partial frames");
+ avist->sample_requested = 1;
+ }
+ avio_wl32(pb, audio_segm_size / au_ssize); /* dwDuration (sample
count) */
+ } else
+ avio_wl32(pb, avist->indexes.entry); /* dwDuration (packet count)
*/
avio_seek(pb, pos, SEEK_SET);
}
--
1.9.1
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