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FFmpeg/libavdevice/decklink_enc.cpp

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/*
* Blackmagic DeckLink output
* Copyright (c) 2013-2014 Ramiro Polla
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <atomic>
using std::atomic;
/* Include internal.h first to avoid conflict between winsock.h (used by
* DeckLink headers) and winsock2.h (used by libavformat) in MSVC++ builds */
extern "C" {
#include "libavformat/internal.h"
}
#include <DeckLinkAPI.h>
extern "C" {
#include "libavformat/avformat.h"
#include "libavutil/imgutils.h"
#include "avdevice.h"
}
#include "decklink_common.h"
#include "decklink_enc.h"
#if CONFIG_LIBKLVANC
#include "libklvanc/vanc.h"
#include "libklvanc/vanc-lines.h"
#include "libklvanc/pixels.h"
#endif
/* DeckLink callback class declaration */
class decklink_frame : public IDeckLinkVideoFrame
{
public:
decklink_frame(struct decklink_ctx *ctx, AVFrame *avframe, AVCodecID codec_id, int height, int width) :
_ctx(ctx), _avframe(avframe), _avpacket(NULL), _codec_id(codec_id), _ancillary(NULL), _height(height), _width(width), _refs(1) { }
decklink_frame(struct decklink_ctx *ctx, AVPacket *avpacket, AVCodecID codec_id, int height, int width) :
_ctx(ctx), _avframe(NULL), _avpacket(avpacket), _codec_id(codec_id), _ancillary(NULL), _height(height), _width(width), _refs(1) { }
virtual long STDMETHODCALLTYPE GetWidth (void) { return _width; }
virtual long STDMETHODCALLTYPE GetHeight (void) { return _height; }
virtual long STDMETHODCALLTYPE GetRowBytes (void)
{
if (_codec_id == AV_CODEC_ID_WRAPPED_AVFRAME)
return _avframe->linesize[0] < 0 ? -_avframe->linesize[0] : _avframe->linesize[0];
else
return ((GetWidth() + 47) / 48) * 128;
}
virtual BMDPixelFormat STDMETHODCALLTYPE GetPixelFormat(void)
{
if (_codec_id == AV_CODEC_ID_WRAPPED_AVFRAME)
return bmdFormat8BitYUV;
else
return bmdFormat10BitYUV;
}
virtual BMDFrameFlags STDMETHODCALLTYPE GetFlags (void)
{
if (_codec_id == AV_CODEC_ID_WRAPPED_AVFRAME)
return _avframe->linesize[0] < 0 ? bmdFrameFlagFlipVertical : bmdFrameFlagDefault;
else
return bmdFrameFlagDefault;
}
virtual HRESULT STDMETHODCALLTYPE GetBytes (void **buffer)
{
if (_codec_id == AV_CODEC_ID_WRAPPED_AVFRAME) {
if (_avframe->linesize[0] < 0)
*buffer = (void *)(_avframe->data[0] + _avframe->linesize[0] * (_avframe->height - 1));
else
*buffer = (void *)(_avframe->data[0]);
} else {
*buffer = (void *)(_avpacket->data);
}
return S_OK;
}
virtual HRESULT STDMETHODCALLTYPE GetTimecode (BMDTimecodeFormat format, IDeckLinkTimecode **timecode) { return S_FALSE; }
virtual HRESULT STDMETHODCALLTYPE GetAncillaryData(IDeckLinkVideoFrameAncillary **ancillary)
{
*ancillary = _ancillary;
if (_ancillary) {
_ancillary->AddRef();
return S_OK;
} else {
return S_FALSE;
}
}
virtual HRESULT STDMETHODCALLTYPE SetAncillaryData(IDeckLinkVideoFrameAncillary *ancillary)
{
if (_ancillary)
_ancillary->Release();
_ancillary = ancillary;
_ancillary->AddRef();
return S_OK;
}
virtual HRESULT STDMETHODCALLTYPE QueryInterface(REFIID iid, LPVOID *ppv) { return E_NOINTERFACE; }
virtual ULONG STDMETHODCALLTYPE AddRef(void) { return ++_refs; }
virtual ULONG STDMETHODCALLTYPE Release(void)
{
int ret = --_refs;
if (!ret) {
av_frame_free(&_avframe);
av_packet_free(&_avpacket);
if (_ancillary)
_ancillary->Release();
delete this;
}
return ret;
}
struct decklink_ctx *_ctx;
AVFrame *_avframe;
AVPacket *_avpacket;
AVCodecID _codec_id;
IDeckLinkVideoFrameAncillary *_ancillary;
int _height;
int _width;
private:
std::atomic<int> _refs;
};
class decklink_output_callback : public IDeckLinkVideoOutputCallback
{
public:
virtual HRESULT STDMETHODCALLTYPE ScheduledFrameCompleted(IDeckLinkVideoFrame *_frame, BMDOutputFrameCompletionResult result)
{
decklink_frame *frame = static_cast<decklink_frame *>(_frame);
struct decklink_ctx *ctx = frame->_ctx;
if (frame->_avframe)
av_frame_unref(frame->_avframe);
if (frame->_avpacket)
av_packet_unref(frame->_avpacket);
pthread_mutex_lock(&ctx->mutex);
ctx->frames_buffer_available_spots++;
pthread_cond_broadcast(&ctx->cond);
pthread_mutex_unlock(&ctx->mutex);
return S_OK;
}
virtual HRESULT STDMETHODCALLTYPE ScheduledPlaybackHasStopped(void) { return S_OK; }
virtual HRESULT STDMETHODCALLTYPE QueryInterface(REFIID iid, LPVOID *ppv) { return E_NOINTERFACE; }
virtual ULONG STDMETHODCALLTYPE AddRef(void) { return 1; }
virtual ULONG STDMETHODCALLTYPE Release(void) { return 1; }
};
static int decklink_setup_video(AVFormatContext *avctx, AVStream *st)
{
struct decklink_cctx *cctx = (struct decklink_cctx *)avctx->priv_data;
struct decklink_ctx *ctx = (struct decklink_ctx *)cctx->ctx;
AVCodecParameters *c = st->codecpar;
if (ctx->video) {
av_log(avctx, AV_LOG_ERROR, "Only one video stream is supported!\n");
return -1;
}
if (c->codec_id == AV_CODEC_ID_WRAPPED_AVFRAME) {
if (c->format != AV_PIX_FMT_UYVY422) {
av_log(avctx, AV_LOG_ERROR, "Unsupported pixel format!"
" Only AV_PIX_FMT_UYVY422 is supported.\n");
return -1;
}
ctx->raw_format = bmdFormat8BitYUV;
} else if (c->codec_id != AV_CODEC_ID_V210) {
av_log(avctx, AV_LOG_ERROR, "Unsupported codec type!"
" Only V210 and wrapped frame with AV_PIX_FMT_UYVY422 are supported.\n");
return -1;
} else {
ctx->raw_format = bmdFormat10BitYUV;
}
if (ff_decklink_set_configs(avctx, DIRECTION_OUT) < 0) {
av_log(avctx, AV_LOG_ERROR, "Could not set output configuration\n");
return -1;
}
if (ff_decklink_set_format(avctx, c->width, c->height,
st->time_base.num, st->time_base.den, c->field_order)) {
av_log(avctx, AV_LOG_ERROR, "Unsupported video size, framerate or field order!"
" Check available formats with -list_formats 1.\n");
return -1;
}
if (ctx->supports_vanc && ctx->dlo->EnableVideoOutput(ctx->bmd_mode, bmdVideoOutputVANC) != S_OK) {
av_log(avctx, AV_LOG_WARNING, "Could not enable video output with VANC! Trying without...\n");
ctx->supports_vanc = 0;
}
if (!ctx->supports_vanc && ctx->dlo->EnableVideoOutput(ctx->bmd_mode, bmdVideoOutputFlagDefault) != S_OK) {
av_log(avctx, AV_LOG_ERROR, "Could not enable video output!\n");
return -1;
}
/* Set callback. */
ctx->output_callback = new decklink_output_callback();
ctx->dlo->SetScheduledFrameCompletionCallback(ctx->output_callback);
ctx->frames_preroll = st->time_base.den * ctx->preroll;
if (st->time_base.den > 1000)
ctx->frames_preroll /= 1000;
/* Buffer twice as many frames as the preroll. */
ctx->frames_buffer = ctx->frames_preroll * 2;
ctx->frames_buffer = FFMIN(ctx->frames_buffer, 60);
pthread_mutex_init(&ctx->mutex, NULL);
pthread_cond_init(&ctx->cond, NULL);
ctx->frames_buffer_available_spots = ctx->frames_buffer;
av_log(avctx, AV_LOG_DEBUG, "output: %s, preroll: %d, frames buffer size: %d\n",
avctx->url, ctx->frames_preroll, ctx->frames_buffer);
/* The device expects the framerate to be fixed. */
avpriv_set_pts_info(st, 64, st->time_base.num, st->time_base.den);
ctx->video = 1;
return 0;
}
static int decklink_setup_audio(AVFormatContext *avctx, AVStream *st)
{
struct decklink_cctx *cctx = (struct decklink_cctx *)avctx->priv_data;
struct decklink_ctx *ctx = (struct decklink_ctx *)cctx->ctx;
AVCodecParameters *c = st->codecpar;
if (ctx->audio) {
av_log(avctx, AV_LOG_ERROR, "Only one audio stream is supported!\n");
return -1;
}
if (c->sample_rate != 48000) {
av_log(avctx, AV_LOG_ERROR, "Unsupported sample rate!"
" Only 48kHz is supported.\n");
return -1;
}
if (c->channels != 2 && c->channels != 8 && c->channels != 16) {
av_log(avctx, AV_LOG_ERROR, "Unsupported number of channels!"
" Only 2, 8 or 16 channels are supported.\n");
return -1;
}
if (ctx->dlo->EnableAudioOutput(bmdAudioSampleRate48kHz,
bmdAudioSampleType16bitInteger,
c->channels,
bmdAudioOutputStreamTimestamped) != S_OK) {
av_log(avctx, AV_LOG_ERROR, "Could not enable audio output!\n");
return -1;
}
if (ctx->dlo->BeginAudioPreroll() != S_OK) {
av_log(avctx, AV_LOG_ERROR, "Could not begin audio preroll!\n");
return -1;
}
/* The device expects the sample rate to be fixed. */
avpriv_set_pts_info(st, 64, 1, c->sample_rate);
ctx->channels = c->channels;
ctx->audio = 1;
return 0;
}
av_cold int ff_decklink_write_trailer(AVFormatContext *avctx)
{
struct decklink_cctx *cctx = (struct decklink_cctx *)avctx->priv_data;
struct decklink_ctx *ctx = (struct decklink_ctx *)cctx->ctx;
if (ctx->playback_started) {
BMDTimeValue actual;
ctx->dlo->StopScheduledPlayback(ctx->last_pts * ctx->bmd_tb_num,
&actual, ctx->bmd_tb_den);
ctx->dlo->DisableVideoOutput();
if (ctx->audio)
ctx->dlo->DisableAudioOutput();
}
ff_decklink_cleanup(avctx);
if (ctx->output_callback)
delete ctx->output_callback;
pthread_mutex_destroy(&ctx->mutex);
pthread_cond_destroy(&ctx->cond);
#if CONFIG_LIBKLVANC
klvanc_context_destroy(ctx->vanc_ctx);
#endif
av_freep(&cctx->ctx);
return 0;
}
#if CONFIG_LIBKLVANC
static void construct_cc(AVFormatContext *avctx, struct decklink_ctx *ctx,
AVPacket *pkt, struct klvanc_line_set_s *vanc_lines)
{
struct klvanc_packet_eia_708b_s *cdp;
uint16_t *cdp_words;
uint16_t len;
uint8_t cc_count;
int size, ret, i;
const uint8_t *data = av_packet_get_side_data(pkt, AV_PKT_DATA_A53_CC, &size);
if (!data)
return;
cc_count = size / 3;
ret = klvanc_create_eia708_cdp(&cdp);
if (ret)
return;
ret = klvanc_set_framerate_EIA_708B(cdp, ctx->bmd_tb_num, ctx->bmd_tb_den);
if (ret) {
av_log(avctx, AV_LOG_ERROR, "Invalid framerate specified: %lld/%lld\n",
ctx->bmd_tb_num, ctx->bmd_tb_den);
klvanc_destroy_eia708_cdp(cdp);
return;
}
if (cc_count > KLVANC_MAX_CC_COUNT) {
av_log(avctx, AV_LOG_ERROR, "Illegal cc_count received: %d\n", cc_count);
cc_count = KLVANC_MAX_CC_COUNT;
}
/* CC data */
cdp->header.ccdata_present = 1;
cdp->header.caption_service_active = 1;
cdp->ccdata.cc_count = cc_count;
for (i = 0; i < cc_count; i++) {
if (data [3*i] & 0x04)
cdp->ccdata.cc[i].cc_valid = 1;
cdp->ccdata.cc[i].cc_type = data[3*i] & 0x03;
cdp->ccdata.cc[i].cc_data[0] = data[3*i+1];
cdp->ccdata.cc[i].cc_data[1] = data[3*i+2];
}
klvanc_finalize_EIA_708B(cdp, ctx->cdp_sequence_num++);
ret = klvanc_convert_EIA_708B_to_words(cdp, &cdp_words, &len);
klvanc_destroy_eia708_cdp(cdp);
if (ret != 0) {
av_log(avctx, AV_LOG_ERROR, "Failed converting 708 packet to words\n");
return;
}
ret = klvanc_line_insert(ctx->vanc_ctx, vanc_lines, cdp_words, len, 11, 0);
free(cdp_words);
if (ret != 0) {
av_log(avctx, AV_LOG_ERROR, "VANC line insertion failed\n");
return;
}
}
static int decklink_construct_vanc(AVFormatContext *avctx, struct decklink_ctx *ctx,
AVPacket *pkt, decklink_frame *frame)
{
struct klvanc_line_set_s vanc_lines = { 0 };
int ret = 0, i;
if (!ctx->supports_vanc)
return 0;
construct_cc(avctx, ctx, pkt, &vanc_lines);
IDeckLinkVideoFrameAncillary *vanc;
int result = ctx->dlo->CreateAncillaryData(bmdFormat10BitYUV, &vanc);
if (result != S_OK) {
av_log(avctx, AV_LOG_ERROR, "Failed to create vanc\n");
ret = AVERROR(EIO);
goto done;
}
/* Now that we've got all the VANC lines in a nice orderly manner, generate the
final VANC sections for the Decklink output */
for (i = 0; i < vanc_lines.num_lines; i++) {
struct klvanc_line_s *line = vanc_lines.lines[i];
int real_line;
void *buf;
if (!line)
break;
/* FIXME: include hack for certain Decklink cards which mis-represent
line numbers for pSF frames */
real_line = line->line_number;
result = vanc->GetBufferForVerticalBlankingLine(real_line, &buf);
if (result != S_OK) {
av_log(avctx, AV_LOG_ERROR, "Failed to get VANC line %d: %d", real_line, result);
continue;
}
/* Generate the full line taking into account all VANC packets on that line */
result = klvanc_generate_vanc_line_v210(ctx->vanc_ctx, line, (uint8_t *) buf,
ctx->bmd_width);
if (result) {
av_log(avctx, AV_LOG_ERROR, "Failed to generate VANC line\n");
continue;
}
}
result = frame->SetAncillaryData(vanc);
vanc->Release();
if (result != S_OK) {
av_log(avctx, AV_LOG_ERROR, "Failed to set vanc: %d", result);
ret = AVERROR(EIO);
}
done:
for (i = 0; i < vanc_lines.num_lines; i++)
klvanc_line_free(vanc_lines.lines[i]);
return ret;
}
#endif
static int decklink_write_video_packet(AVFormatContext *avctx, AVPacket *pkt)
{
struct decklink_cctx *cctx = (struct decklink_cctx *)avctx->priv_data;
struct decklink_ctx *ctx = (struct decklink_ctx *)cctx->ctx;
AVStream *st = avctx->streams[pkt->stream_index];
AVFrame *avframe = NULL, *tmp = (AVFrame *)pkt->data;
AVPacket *avpacket = NULL;
decklink_frame *frame;
buffercount_type buffered;
HRESULT hr;
if (st->codecpar->codec_id == AV_CODEC_ID_WRAPPED_AVFRAME) {
if (tmp->format != AV_PIX_FMT_UYVY422 ||
tmp->width != ctx->bmd_width ||
tmp->height != ctx->bmd_height) {
av_log(avctx, AV_LOG_ERROR, "Got a frame with invalid pixel format or dimension.\n");
return AVERROR(EINVAL);
}
avframe = av_frame_clone(tmp);
if (!avframe) {
av_log(avctx, AV_LOG_ERROR, "Could not clone video frame.\n");
return AVERROR(EIO);
}
frame = new decklink_frame(ctx, avframe, st->codecpar->codec_id, avframe->height, avframe->width);
} else {
avpacket = av_packet_clone(pkt);
if (!avpacket) {
av_log(avctx, AV_LOG_ERROR, "Could not clone video frame.\n");
return AVERROR(EIO);
}
frame = new decklink_frame(ctx, avpacket, st->codecpar->codec_id, ctx->bmd_height, ctx->bmd_width);
#if CONFIG_LIBKLVANC
if (decklink_construct_vanc(avctx, ctx, pkt, frame))
av_log(avctx, AV_LOG_ERROR, "Failed to construct VANC\n");
#endif
}
if (!frame) {
av_log(avctx, AV_LOG_ERROR, "Could not create new frame.\n");
av_frame_free(&avframe);
av_packet_free(&avpacket);
return AVERROR(EIO);
}
/* Always keep at most one second of frames buffered. */
pthread_mutex_lock(&ctx->mutex);
while (ctx->frames_buffer_available_spots == 0) {
pthread_cond_wait(&ctx->cond, &ctx->mutex);
}
ctx->frames_buffer_available_spots--;
pthread_mutex_unlock(&ctx->mutex);
/* Schedule frame for playback. */
hr = ctx->dlo->ScheduleVideoFrame((class IDeckLinkVideoFrame *) frame,
pkt->pts * ctx->bmd_tb_num,
ctx->bmd_tb_num, ctx->bmd_tb_den);
/* Pass ownership to DeckLink, or release on failure */
frame->Release();
if (hr != S_OK) {
av_log(avctx, AV_LOG_ERROR, "Could not schedule video frame."
" error %08x.\n", (uint32_t) hr);
return AVERROR(EIO);
}
ctx->dlo->GetBufferedVideoFrameCount(&buffered);
av_log(avctx, AV_LOG_DEBUG, "Buffered video frames: %d.\n", (int) buffered);
if (pkt->pts > 2 && buffered <= 2)
av_log(avctx, AV_LOG_WARNING, "There are not enough buffered video frames."
" Video may misbehave!\n");
/* Preroll video frames. */
if (!ctx->playback_started && pkt->pts > ctx->frames_preroll) {
av_log(avctx, AV_LOG_DEBUG, "Ending audio preroll.\n");
if (ctx->audio && ctx->dlo->EndAudioPreroll() != S_OK) {
av_log(avctx, AV_LOG_ERROR, "Could not end audio preroll!\n");
return AVERROR(EIO);
}
av_log(avctx, AV_LOG_DEBUG, "Starting scheduled playback.\n");
if (ctx->dlo->StartScheduledPlayback(0, ctx->bmd_tb_den, 1.0) != S_OK) {
av_log(avctx, AV_LOG_ERROR, "Could not start scheduled playback!\n");
return AVERROR(EIO);
}
ctx->playback_started = 1;
}
return 0;
}
static int decklink_write_audio_packet(AVFormatContext *avctx, AVPacket *pkt)
{
struct decklink_cctx *cctx = (struct decklink_cctx *)avctx->priv_data;
struct decklink_ctx *ctx = (struct decklink_ctx *)cctx->ctx;
int sample_count = pkt->size / (ctx->channels << 1);
buffercount_type buffered;
ctx->dlo->GetBufferedAudioSampleFrameCount(&buffered);
if (pkt->pts > 1 && !buffered)
av_log(avctx, AV_LOG_WARNING, "There's no buffered audio."
" Audio will misbehave!\n");
if (ctx->dlo->ScheduleAudioSamples(pkt->data, sample_count, pkt->pts,
bmdAudioSampleRate48kHz, NULL) != S_OK) {
av_log(avctx, AV_LOG_ERROR, "Could not schedule audio samples.\n");
return AVERROR(EIO);
}
return 0;
}
extern "C" {
av_cold int ff_decklink_write_header(AVFormatContext *avctx)
{
struct decklink_cctx *cctx = (struct decklink_cctx *)avctx->priv_data;
struct decklink_ctx *ctx;
unsigned int n;
int ret;
ctx = (struct decklink_ctx *) av_mallocz(sizeof(struct decklink_ctx));
if (!ctx)
return AVERROR(ENOMEM);
ctx->list_devices = cctx->list_devices;
ctx->list_formats = cctx->list_formats;
ctx->preroll = cctx->preroll;
ctx->duplex_mode = cctx->duplex_mode;
cctx->ctx = ctx;
#if CONFIG_LIBKLVANC
if (klvanc_context_create(&ctx->vanc_ctx) < 0) {
av_log(avctx, AV_LOG_ERROR, "Cannot create VANC library context\n");
return AVERROR(ENOMEM);
}
ctx->supports_vanc = 1;
#endif
/* List available devices and exit. */
if (ctx->list_devices) {
ff_decklink_list_devices_legacy(avctx, 0, 1);
return AVERROR_EXIT;
}
ret = ff_decklink_init_device(avctx, avctx->url);
if (ret < 0)
return ret;
/* Get output device. */
if (ctx->dl->QueryInterface(IID_IDeckLinkOutput, (void **) &ctx->dlo) != S_OK) {
av_log(avctx, AV_LOG_ERROR, "Could not open output device from '%s'\n",
avctx->url);
ret = AVERROR(EIO);
goto error;
}
/* List supported formats. */
if (ctx->list_formats) {
ff_decklink_list_formats(avctx);
ret = AVERROR_EXIT;
goto error;
}
/* Setup streams. */
ret = AVERROR(EIO);
for (n = 0; n < avctx->nb_streams; n++) {
AVStream *st = avctx->streams[n];
AVCodecParameters *c = st->codecpar;
if (c->codec_type == AVMEDIA_TYPE_AUDIO) {
if (decklink_setup_audio(avctx, st))
goto error;
} else if (c->codec_type == AVMEDIA_TYPE_VIDEO) {
if (decklink_setup_video(avctx, st))
goto error;
} else {
av_log(avctx, AV_LOG_ERROR, "Unsupported stream type.\n");
goto error;
}
}
return 0;
error:
ff_decklink_cleanup(avctx);
return ret;
}
int ff_decklink_write_packet(AVFormatContext *avctx, AVPacket *pkt)
{
struct decklink_cctx *cctx = (struct decklink_cctx *)avctx->priv_data;
struct decklink_ctx *ctx = (struct decklink_ctx *)cctx->ctx;
AVStream *st = avctx->streams[pkt->stream_index];
ctx->last_pts = FFMAX(ctx->last_pts, pkt->pts);
if (st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO)
return decklink_write_video_packet(avctx, pkt);
else if (st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO)
return decklink_write_audio_packet(avctx, pkt);
return AVERROR(EIO);
}
int ff_decklink_list_output_devices(AVFormatContext *avctx, struct AVDeviceInfoList *device_list)
{
return ff_decklink_list_devices(avctx, device_list, 0, 1);
}
} /* extern "C" */