[FFmpeg-devel] [PATCH] libavdevice/decklink: 32 bit audio support
Dave Rice
dave at dericed.com
Tue Oct 17 16:22:27 EEST 2017
Hi Paul,
> On Oct 16, 2017, at 3:56 PM, Paul B Mahol <onemda at gmail.com> wrote:
>
> On 10/16/17, Dave Rice <dave at dericed.com <mailto:dave at dericed.com>> wrote:
>> Hi,
>>
>> I tested this with my Ultrastudio Express and confirmed that I'm getting
>> higher bit depth recordings with the abitscope filter. This patch adds an
>> option to get 32 bit audio as an input with the decklink device (beforehand
>> only 16 bit audio was supported). This resolves
>> http://trac.ffmpeg.org/ticket/6708 and is partly based upon Georg
>> Lippitisch's earlier draft at
>> https://ffmpeg.org/pipermail/ffmpeg-devel/2015-January/167649.html.
>>
>>
>> From fbf2bd40471c8fa35374bb1a51c51a3f4f36b992 Mon Sep 17 00:00:00 2001
>> From: Dave Rice <dave at dericed.com>
>> Date: Thu, 12 Oct 2017 13:40:59 -0400
>> Subject: [PATCH] libavdevice/decklink: 32 bit audio support
>>
>> Partially based upon Georg Lippitsch's patch at
>> https://ffmpeg.org/pipermail/ffmpeg-devel/2015-January/167649.html.
>> ---
>> libavdevice/decklink_common.h | 1 +
>> libavdevice/decklink_common_c.h | 1 +
>> libavdevice/decklink_dec.cpp | 17 ++++++++++++++---
>> libavdevice/decklink_dec_c.c | 1 +
>> 4 files changed, 17 insertions(+), 3 deletions(-)
>>
>> diff --git a/libavdevice/decklink_common.h b/libavdevice/decklink_common.h
>> index 6b2525fb53..b6acb01bb9 100644
>> --- a/libavdevice/decklink_common.h
>> +++ b/libavdevice/decklink_common.h
>> @@ -97,6 +97,7 @@ struct decklink_ctx {
>> int frames_buffer_available_spots;
>>
>> int channels;
>> + int audio_depth;
>> };
>>
>> typedef enum { DIRECTION_IN, DIRECTION_OUT} decklink_direction_t;
>> diff --git a/libavdevice/decklink_common_c.h
>> b/libavdevice/decklink_common_c.h
>> index 5616ab32f9..368ac259e4 100644
>> --- a/libavdevice/decklink_common_c.h
>> +++ b/libavdevice/decklink_common_c.h
>> @@ -42,6 +42,7 @@ struct decklink_cctx {
>> double preroll;
>> int v210;
>> int audio_channels;
>> + int audio_depth;
>> int duplex_mode;
>> DecklinkPtsSource audio_pts_source;
>> DecklinkPtsSource video_pts_source;
>> diff --git a/libavdevice/decklink_dec.cpp b/libavdevice/decklink_dec.cpp
>> index d9ac01ac91..7e97d5f064 100644
>> --- a/libavdevice/decklink_dec.cpp
>> +++ b/libavdevice/decklink_dec.cpp
>> @@ -771,7 +771,7 @@ HRESULT
>> decklink_input_callback::VideoInputFrameArrived(
>> av_init_packet(&pkt);
>>
>> //hack among hacks
>> - pkt.size = audioFrame->GetSampleFrameCount() *
>> ctx->audio_st->codecpar->channels * (16 / 8);
>> + pkt.size = audioFrame->GetSampleFrameCount() *
>> ctx->audio_st->codecpar->channels * (ctx->audio_depth / 8);
>> audioFrame->GetBytes(&audioFrameBytes);
>> audioFrame->GetPacketTime(&audio_pts,
>> ctx->audio_st->time_base.den);
>> pkt.pts = get_pkt_pts(videoFrame, audioFrame, wallclock,
>> ctx->audio_pts_source, ctx->audio_st->time_base, &initial_audio_pts);
>> @@ -854,6 +854,7 @@ av_cold int ff_decklink_read_header(AVFormatContext
>> *avctx)
>> ctx->audio_pts_source = cctx->audio_pts_source;
>> ctx->video_pts_source = cctx->video_pts_source;
>> ctx->draw_bars = cctx->draw_bars;
>> + ctx->audio_depth = cctx->audio_depth;
>> cctx->ctx = ctx;
>>
>> /* Check audio channel option for valid values: 2, 8 or 16 */
>> @@ -866,6 +867,16 @@ av_cold int ff_decklink_read_header(AVFormatContext
>> *avctx)
>> av_log(avctx, AV_LOG_ERROR, "Value of channels option must be
>> one of 2, 8 or 16\n");
>> return AVERROR(EINVAL);
>> }
>> +
>> + /* Check audio bit depth option for valid values: 16 or 32 */
>> + switch (cctx->audio_depth) {
>> + case 16:
>> + case 32:
>> + break;
>> + default:
>> + av_log(avctx, AV_LOG_ERROR, "Value for audio bit depth option
>> must be either 16 or 32\n");
>> + return AVERROR(EINVAL);
>
> This message is redundant with AVOptions, User should be able to
> select only 16 or 32,
> see bellow.
>
>> + }
>>
>> /* List available devices. */
>> if (ctx->list_devices) {
>> @@ -930,7 +941,7 @@ av_cold int ff_decklink_read_header(AVFormatContext
>> *avctx)
>> goto error;
>> }
>> st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
>> - st->codecpar->codec_id = AV_CODEC_ID_PCM_S16LE;
>> + st->codecpar->codec_id = cctx->audio_depth == 32 ?
>> AV_CODEC_ID_PCM_S32LE : AV_CODEC_ID_PCM_S16LE;
>> st->codecpar->sample_rate = bmdAudioSampleRate48kHz;
>> st->codecpar->channels = cctx->audio_channels;
>> avpriv_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
>> @@ -1021,7 +1032,7 @@ av_cold int ff_decklink_read_header(AVFormatContext
>> *avctx)
>> }
>>
>> av_log(avctx, AV_LOG_VERBOSE, "Using %d input audio channels\n",
>> ctx->audio_st->codecpar->channels);
>> - result = ctx->dli->EnableAudioInput(bmdAudioSampleRate48kHz,
>> bmdAudioSampleType16bitInteger, ctx->audio_st->codecpar->channels);
>> + result = ctx->dli->EnableAudioInput(bmdAudioSampleRate48kHz,
>> cctx->audio_depth == 32 ? bmdAudioSampleType32bitInteger :
>> bmdAudioSampleType16bitInteger, ctx->audio_st->codecpar->channels);
>>
>> if (result != S_OK) {
>> av_log(avctx, AV_LOG_ERROR, "Cannot enable audio input\n");
>> diff --git a/libavdevice/decklink_dec_c.c b/libavdevice/decklink_dec_c.c
>> index 1127d23ada..1c6d826945 100644
>> --- a/libavdevice/decklink_dec_c.c
>> +++ b/libavdevice/decklink_dec_c.c
>> @@ -72,6 +72,7 @@ static const AVOption options[] = {
>> { "wallclock", NULL, 0,
>> AV_OPT_TYPE_CONST, { .i64 = PTS_SRC_WALLCLOCK}, 0, 0, DEC, "pts_source"},
>> { "draw_bars", "draw bars on signal loss" , OFFSET(draw_bars),
>> AV_OPT_TYPE_BOOL, { .i64 = 1}, 0, 1, DEC },
>> { "queue_size", "input queue buffer size", OFFSET(queue_size),
>> AV_OPT_TYPE_INT64, { .i64 = (1024 * 1024 * 1024)}, 0, INT64_MAX, DEC },
>> + { "audio_depth", "audio bitdepth (16 or 32)", OFFSET(audio_depth),
>> AV_OPT_TYPE_INT, { .i64 = 16}, 16, 32, DEC },
>
> Use AV_OPT_ ENUM instead.
I don't see there to be an AV_OPT_TYPE_ENUM. Could you point out how this works from an example? Alternatively since the decklink sdk only supports 2 bit depths (16 and 32), I could use a boolean here if that makes more sense.
Dave Rice
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