#include "ffmpeg_util.h"
#include "flags.h"
#include "image_input.h"
+#include "ref_counted_frame.h"
#include "timebase.h"
#define FRAME_SIZE (8 << 20) // 8 MB.
FFmpegCapture::FFmpegCapture(const string &filename, unsigned width, unsigned height)
: filename(filename), width(width), height(height), video_timebase{1, 1}
{
- // Not really used for anything.
description = "Video: " + filename;
+ last_frame = steady_clock::now();
+
avformat_network_init(); // In case someone wants this.
}
pthread_setname_np(pthread_self(), thread_name);
while (!producer_thread_should_quit.should_quit()) {
- string pathname = search_for_file(filename);
- if (filename.empty()) {
- fprintf(stderr, "%s not found, sleeping one second and trying again...\n", filename.c_str());
+ string filename_copy;
+ {
+ lock_guard<mutex> lock(filename_mu);
+ filename_copy = filename;
+ }
+
+ string pathname = search_for_file(filename_copy);
+ if (pathname.empty()) {
+ fprintf(stderr, "%s not found, sleeping one second and trying again...\n", filename_copy.c_str());
send_disconnected_frame();
producer_thread_should_quit.sleep_for(seconds(1));
continue;
}
+ should_interrupt = false;
if (!play_video(pathname)) {
// Error.
fprintf(stderr, "Error when playing %s, sleeping one second and trying again...\n", pathname.c_str());
VideoFormat video_format;
video_format.width = width;
video_format.height = height;
- video_format.stride = width * 4;
video_format.frame_rate_nom = 60;
video_format.frame_rate_den = 1;
video_format.is_connected = false;
-
- video_frame.len = width * height * 4;
- memset(video_frame.data, 0, video_frame.len);
+ if (pixel_format == bmusb::PixelFormat_8BitBGRA) {
+ video_format.stride = width * 4;
+ video_frame.len = width * height * 4;
+ memset(video_frame.data, 0, video_frame.len);
+ } else {
+ video_format.stride = width;
+ current_frame_ycbcr_format.luma_coefficients = YCBCR_REC_709;
+ current_frame_ycbcr_format.full_range = true;
+ current_frame_ycbcr_format.num_levels = 256;
+ current_frame_ycbcr_format.chroma_subsampling_x = 2;
+ current_frame_ycbcr_format.chroma_subsampling_y = 2;
+ current_frame_ycbcr_format.cb_x_position = 0.0f;
+ current_frame_ycbcr_format.cb_y_position = 0.0f;
+ current_frame_ycbcr_format.cr_x_position = 0.0f;
+ current_frame_ycbcr_format.cr_y_position = 0.0f;
+ video_frame.len = width * height * 2;
+ memset(video_frame.data, 0, width * height);
+ memset(video_frame.data + width * height, 128, width * height); // Valid for both NV12 and planar.
+ }
frame_callback(-1, AVRational{1, TIMEBASE}, -1, AVRational{1, TIMEBASE}, timecode++,
video_frame, /*video_offset=*/0, video_format,
FrameAllocator::Frame(), /*audio_offset=*/0, AudioFormat());
+ last_frame_was_connected = false;
}
}
last_modified = buf.st_mtim;
}
- auto format_ctx = avformat_open_input_unique(pathname.c_str(), nullptr, nullptr);
+ AVDictionary *opts = nullptr;
+ av_dict_set(&opts, "fflags", "nobuffer", 0);
+
+ auto format_ctx = avformat_open_input_unique(pathname.c_str(), nullptr, &opts, AVIOInterruptCB{ &FFmpegCapture::interrupt_cb_thunk, this });
if (format_ctx == nullptr) {
fprintf(stderr, "%s: Error opening file\n", pathname.c_str());
return false;
video_codec_ctx.get(), avcodec_close);
// Open audio decoder, if we have audio.
- AVCodecContextWithDeleter audio_codec_ctx = avcodec_alloc_context3_unique(nullptr);
+ AVCodecContextWithDeleter audio_codec_ctx;
if (audio_stream_index != -1) {
+ audio_codec_ctx = avcodec_alloc_context3_unique(nullptr);
const AVCodecParameters *audio_codecpar = format_ctx->streams[audio_stream_index]->codecpar;
audio_timebase = format_ctx->streams[audio_stream_index]->time_base;
if (avcodec_parameters_to_context(audio_codec_ctx.get(), audio_codecpar) < 0) {
internal_rewind();
// Main loop.
+ bool first_frame = true;
while (!producer_thread_should_quit.should_quit()) {
if (process_queued_commands(format_ctx.get(), pathname, last_modified, /*rewound=*/nullptr)) {
return true;
}
- FrameAllocator::Frame audio_frame = audio_frame_allocator->alloc_frame();
+ UniqueFrame audio_frame = audio_frame_allocator->alloc_frame();
AudioFormat audio_format;
int64_t audio_pts;
bool error;
AVFrameWithDeleter frame = decode_frame(format_ctx.get(), video_codec_ctx.get(), audio_codec_ctx.get(),
- pathname, video_stream_index, audio_stream_index, &audio_frame, &audio_format, &audio_pts, &error);
+ pathname, video_stream_index, audio_stream_index, audio_frame.get(), &audio_format, &audio_pts, &error);
if (error) {
return false;
}
fprintf(stderr, "%s: Rewind failed, not looping.\n", pathname.c_str());
return true;
}
+ if (video_codec_ctx != nullptr) {
+ avcodec_flush_buffers(video_codec_ctx.get());
+ }
+ if (audio_codec_ctx != nullptr) {
+ avcodec_flush_buffers(audio_codec_ctx.get());
+ }
// If the file has changed since last time, return to get it reloaded.
// Note that depending on how you move the file into place, you might
// end up corrupting the one you're already playing, so this path
}
VideoFormat video_format = construct_video_format(frame.get(), video_timebase);
- FrameAllocator::Frame video_frame = make_video_frame(frame.get(), pathname, &error);
+ UniqueFrame video_frame = make_video_frame(frame.get(), pathname, &error);
if (error) {
return false;
}
pts_origin = frame->pts;
}
next_frame_start = compute_frame_start(frame->pts, pts_origin, video_timebase, start, rate);
- video_frame.received_timestamp = next_frame_start;
+ if (first_frame && last_frame_was_connected) {
+ // If reconnect took more than one second, this is probably a live feed,
+ // and we should reset the resampler. (Or the rate is really, really low,
+ // in which case a reset on the first frame is fine anyway.)
+ if (duration<double>(next_frame_start - last_frame).count() >= 1.0) {
+ last_frame_was_connected = false;
+ }
+ }
+ video_frame->received_timestamp = next_frame_start;
+
+ // The easiest way to get all the rate conversions etc. right is to move the
+ // audio PTS into the video PTS timebase and go from there. (We'll get some
+ // rounding issues, but they should not be a big problem.)
+ int64_t audio_pts_as_video_pts = av_rescale_q(audio_pts, audio_timebase, video_timebase);
+ audio_frame->received_timestamp = compute_frame_start(audio_pts_as_video_pts, pts_origin, video_timebase, start, rate);
+
+ if (audio_frame->len != 0) {
+ // The received timestamps in Nageru are measured after we've just received the frame.
+ // However, pts (especially audio pts) is at the _beginning_ of the frame.
+ // If we have locked audio, the distinction doesn't really matter, as pts is
+ // on a relative scale and a fixed offset is fine. But if we don't, we will have
+ // a different number of samples each time, which will cause huge audio jitter
+ // and throw off the resampler.
+ //
+ // In a sense, we should have compensated by adding the frame and audio lengths
+ // to video_frame->received_timestamp and audio_frame->received_timestamp respectively,
+ // but that would mean extra waiting in sleep_until(). All we need is that they
+ // are correct relative to each other, though (and to the other frames we send),
+ // so just align the end of the audio frame, and we're fine.
+ size_t num_samples = (audio_frame->len * 8) / audio_format.bits_per_sample / audio_format.num_channels;
+ double offset = double(num_samples) / OUTPUT_FREQUENCY -
+ double(video_format.frame_rate_den) / video_format.frame_rate_nom;
+ audio_frame->received_timestamp += duration_cast<steady_clock::duration>(duration<double>(offset));
+ }
+
+ steady_clock::time_point now = steady_clock::now();
+ if (duration<double>(now - next_frame_start).count() >= 0.1) {
+ // If we don't have enough CPU to keep up, or if we have a live stream
+ // where the initial origin was somehow wrong, we could be behind indefinitely.
+ // In particular, this will give the audio resampler problems as it tries
+ // to speed up to reduce the delay, hitting the low end of the buffer every time.
+ fprintf(stderr, "%s: Playback %.0f ms behind, resetting time scale\n",
+ pathname.c_str(),
+ 1e3 * duration<double>(now - next_frame_start).count());
+ pts_origin = frame->pts;
+ start = next_frame_start = now;
+ timecode += MAX_FPS * 2 + 1;
+ }
bool finished_wakeup = producer_thread_should_quit.sleep_until(next_frame_start);
if (finished_wakeup) {
- if (audio_frame.len > 0) {
+ if (audio_frame->len > 0) {
assert(audio_pts != -1);
}
+ if (!last_frame_was_connected) {
+ // We're recovering from an error (or really slow load, see above).
+ // Make sure to get the audio resampler reset. (This is a hack;
+ // ideally, the frame callback should just accept a way to signal
+ // audio discontinuity.)
+ timecode += MAX_FPS * 2 + 1;
+ }
frame_callback(frame->pts, video_timebase, audio_pts, audio_timebase, timecode++,
- video_frame, 0, video_format,
- audio_frame, 0, audio_format);
+ video_frame.get_and_release(), 0, video_format,
+ audio_frame.get_and_release(), 0, audio_format);
+ first_frame = false;
+ last_frame = steady_clock::now();
+ last_frame_was_connected = true;
break;
} else {
if (producer_thread_should_quit.should_quit()) break;
}
// If we just rewound, drop this frame on the floor and be done.
if (rewound) {
- video_frame_allocator->release_frame(video_frame);
break;
}
// OK, we didn't, so probably a rate change. Recalculate next_frame_start,
AVFrameWithDeleter video_avframe = av_frame_alloc_unique();
bool eof = false;
*audio_pts = -1;
+ bool has_audio = false;
do {
AVPacket pkt;
unique_ptr<AVPacket, decltype(av_packet_unref)*> pkt_cleanup(
return AVFrameWithDeleter(nullptr);
}
} else if (pkt.stream_index == audio_stream_index) {
- if (*audio_pts == -1) {
- *audio_pts = pkt.pts;
- }
+ has_audio = true;
if (avcodec_send_packet(audio_codec_ctx, &pkt) < 0) {
fprintf(stderr, "%s: Cannot send packet to audio codec.\n", pathname.c_str());
*error = true;
}
// Decode audio, if any.
- if (*audio_pts != -1) {
+ if (has_audio) {
for ( ;; ) {
int err = avcodec_receive_frame(audio_codec_ctx, audio_avframe.get());
if (err == 0) {
+ if (*audio_pts == -1) {
+ *audio_pts = audio_avframe->pts;
+ }
convert_audio(audio_avframe.get(), audio_frame, audio_format);
} else if (err == AVERROR(EAGAIN)) {
break;
}
audio_format->num_channels = 2;
+ int64_t channel_layout = audio_avframe->channel_layout;
+ if (channel_layout == 0) {
+ channel_layout = av_get_default_channel_layout(audio_avframe->channels);
+ }
+
if (resampler == nullptr ||
audio_avframe->format != last_src_format ||
dst_format != last_dst_format ||
- av_frame_get_channel_layout(audio_avframe) != last_channel_layout ||
+ channel_layout != last_channel_layout ||
av_frame_get_sample_rate(audio_avframe) != last_sample_rate) {
avresample_free(&resampler);
resampler = avresample_alloc_context();
exit(1);
}
- av_opt_set_int(resampler, "in_channel_layout", av_frame_get_channel_layout(audio_avframe), 0);
+ av_opt_set_int(resampler, "in_channel_layout", channel_layout, 0);
av_opt_set_int(resampler, "out_channel_layout", AV_CH_LAYOUT_STEREO, 0);
av_opt_set_int(resampler, "in_sample_rate", av_frame_get_sample_rate(audio_avframe), 0);
av_opt_set_int(resampler, "out_sample_rate", OUTPUT_FREQUENCY, 0);
last_src_format = AVSampleFormat(audio_avframe->format);
last_dst_format = dst_format;
- last_channel_layout = av_frame_get_channel_layout(audio_avframe);
+ last_channel_layout = channel_layout;
last_sample_rate = av_frame_get_sample_rate(audio_avframe);
}
uint8_t *data = audio_frame->data + audio_frame->len;
int out_samples = avresample_convert(resampler, &data, 0, num_samples_room,
- audio_avframe->data, audio_avframe->linesize[0], audio_avframe->nb_samples);
+ const_cast<uint8_t **>(audio_avframe->data), audio_avframe->linesize[0], audio_avframe->nb_samples);
if (out_samples < 0) {
fprintf(stderr, "Audio conversion failed.\n");
exit(1);
return video_format;
}
-FrameAllocator::Frame FFmpegCapture::make_video_frame(const AVFrame *frame, const string &pathname, bool *error)
+UniqueFrame FFmpegCapture::make_video_frame(const AVFrame *frame, const string &pathname, bool *error)
{
*error = false;
- FrameAllocator::Frame video_frame = video_frame_allocator->alloc_frame();
- if (video_frame.data == nullptr) {
+ UniqueFrame video_frame(video_frame_allocator->alloc_frame());
+ if (video_frame->data == nullptr) {
return video_frame;
}
uint8_t *pic_data[4] = { nullptr, nullptr, nullptr, nullptr };
int linesizes[4] = { 0, 0, 0, 0 };
if (pixel_format == bmusb::PixelFormat_8BitBGRA) {
- pic_data[0] = video_frame.data;
+ pic_data[0] = video_frame->data;
linesizes[0] = width * 4;
- video_frame.len = (width * 4) * height;
+ video_frame->len = (width * 4) * height;
} else if (pixel_format == PixelFormat_NV12) {
- pic_data[0] = video_frame.data;
+ pic_data[0] = video_frame->data;
linesizes[0] = width;
pic_data[1] = pic_data[0] + width * height;
linesizes[1] = width;
- video_frame.len = (width * 2) * height;
+ video_frame->len = (width * 2) * height;
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(sws_dst_format);
current_frame_ycbcr_format = decode_ycbcr_format(desc, frame);
int chroma_width = AV_CEIL_RSHIFT(int(width), desc->log2_chroma_w);
int chroma_height = AV_CEIL_RSHIFT(int(height), desc->log2_chroma_h);
- pic_data[0] = video_frame.data;
+ pic_data[0] = video_frame->data;
linesizes[0] = width;
pic_data[1] = pic_data[0] + width * height;
pic_data[2] = pic_data[1] + chroma_width * chroma_height;
linesizes[2] = chroma_width;
- video_frame.len = width * height + 2 * chroma_width * chroma_height;
+ video_frame->len = width * height + 2 * chroma_width * chroma_height;
current_frame_ycbcr_format = decode_ycbcr_format(desc, frame);
}
return video_frame;
}
+
+int FFmpegCapture::interrupt_cb_thunk(void *unique)
+{
+ return reinterpret_cast<FFmpegCapture *>(unique)->interrupt_cb();
+}
+
+int FFmpegCapture::interrupt_cb()
+{
+ return should_interrupt.load();
+}