1 #include "ffmpeg_capture.h"
13 #include <libavcodec/avcodec.h>
14 #include <libavformat/avformat.h>
15 #include <libavutil/avutil.h>
16 #include <libavutil/error.h>
17 #include <libavutil/frame.h>
18 #include <libavutil/imgutils.h>
19 #include <libavutil/mem.h>
20 #include <libavutil/pixfmt.h>
21 #include <libswscale/swscale.h>
29 #include "bmusb/bmusb.h"
30 #include "ffmpeg_raii.h"
31 #include "ffmpeg_util.h"
33 #include "image_input.h"
35 #define FRAME_SIZE (8 << 20) // 8 MB.
38 using namespace std::chrono;
39 using namespace bmusb;
43 steady_clock::time_point compute_frame_start(int64_t frame_pts, int64_t pts_origin, const AVRational &video_timebase, const steady_clock::time_point &origin, double rate)
45 const duration<double> pts((frame_pts - pts_origin) * double(video_timebase.num) / double(video_timebase.den));
46 return origin + duration_cast<steady_clock::duration>(pts / rate);
49 bool changed_since(const std::string &pathname, const timespec &ts)
55 if (stat(pathname.c_str(), &buf) != 0) {
56 fprintf(stderr, "%s: Couldn't check for new version, leaving the old in place.\n", pathname.c_str());
59 return (buf.st_mtim.tv_sec != ts.tv_sec || buf.st_mtim.tv_nsec != ts.tv_nsec);
64 FFmpegCapture::FFmpegCapture(const string &filename, unsigned width, unsigned height)
65 : filename(filename), width(width), height(height)
67 // Not really used for anything.
68 description = "Video: " + filename;
71 FFmpegCapture::~FFmpegCapture()
73 if (has_dequeue_callbacks) {
74 dequeue_cleanup_callback();
78 void FFmpegCapture::configure_card()
80 if (video_frame_allocator == nullptr) {
81 owned_video_frame_allocator.reset(new MallocFrameAllocator(FRAME_SIZE, NUM_QUEUED_VIDEO_FRAMES));
82 set_video_frame_allocator(owned_video_frame_allocator.get());
84 if (audio_frame_allocator == nullptr) {
85 owned_audio_frame_allocator.reset(new MallocFrameAllocator(65536, NUM_QUEUED_AUDIO_FRAMES));
86 set_audio_frame_allocator(owned_audio_frame_allocator.get());
90 void FFmpegCapture::start_bm_capture()
96 producer_thread_should_quit.unquit();
97 producer_thread = thread(&FFmpegCapture::producer_thread_func, this);
100 void FFmpegCapture::stop_dequeue_thread()
106 producer_thread_should_quit.quit();
107 producer_thread.join();
110 std::map<uint32_t, VideoMode> FFmpegCapture::get_available_video_modes() const
112 // Note: This will never really be shown in the UI.
116 snprintf(buf, sizeof(buf), "%ux%u", width, height);
119 mode.autodetect = false;
121 mode.height = height;
122 mode.frame_rate_num = 60;
123 mode.frame_rate_den = 1;
124 mode.interlaced = false;
126 return {{ 0, mode }};
129 void FFmpegCapture::producer_thread_func()
131 char thread_name[16];
132 snprintf(thread_name, sizeof(thread_name), "FFmpeg_C_%d", card_index);
133 pthread_setname_np(pthread_self(), thread_name);
135 while (!producer_thread_should_quit.should_quit()) {
136 string pathname = search_for_file(filename);
137 if (filename.empty()) {
138 fprintf(stderr, "%s not found, sleeping one second and trying again...\n", filename.c_str());
139 producer_thread_should_quit.sleep_for(seconds(1));
142 if (!play_video(pathname)) {
144 fprintf(stderr, "Error when playing %s, sleeping one second and trying again...\n", pathname.c_str());
145 producer_thread_should_quit.sleep_for(seconds(1));
149 // Probably just EOF, will exit the loop above on next test.
152 if (has_dequeue_callbacks) {
153 dequeue_cleanup_callback();
154 has_dequeue_callbacks = false;
158 bool FFmpegCapture::play_video(const string &pathname)
160 // Note: Call before open, not after; otherwise, there's a race.
161 // (There is now, too, but it tips the correct way. We could use fstat()
162 // if we had the file descriptor.)
163 timespec last_modified;
165 if (stat(pathname.c_str(), &buf) != 0) {
166 // Probably some sort of protocol, so can't stat.
167 last_modified.tv_sec = -1;
169 last_modified = buf.st_mtim;
172 auto format_ctx = avformat_open_input_unique(pathname.c_str(), nullptr, nullptr);
173 if (format_ctx == nullptr) {
174 fprintf(stderr, "%s: Error opening file\n", pathname.c_str());
178 if (avformat_find_stream_info(format_ctx.get(), nullptr) < 0) {
179 fprintf(stderr, "%s: Error finding stream info\n", pathname.c_str());
183 int video_stream_index = find_stream_index(format_ctx.get(), AVMEDIA_TYPE_VIDEO);
184 if (video_stream_index == -1) {
185 fprintf(stderr, "%s: No video stream found\n", pathname.c_str());
189 const AVCodecParameters *codecpar = format_ctx->streams[video_stream_index]->codecpar;
190 AVRational video_timebase = format_ctx->streams[video_stream_index]->time_base;
191 AVCodecContextWithDeleter codec_ctx = avcodec_alloc_context3_unique(nullptr);
192 if (avcodec_parameters_to_context(codec_ctx.get(), codecpar) < 0) {
193 fprintf(stderr, "%s: Cannot fill codec parameters\n", pathname.c_str());
196 AVCodec *codec = avcodec_find_decoder(codecpar->codec_id);
197 if (codec == nullptr) {
198 fprintf(stderr, "%s: Cannot find decoder\n", pathname.c_str());
201 if (avcodec_open2(codec_ctx.get(), codec, nullptr) < 0) {
202 fprintf(stderr, "%s: Cannot open decoder\n", pathname.c_str());
205 unique_ptr<AVCodecContext, decltype(avcodec_close)*> codec_ctx_cleanup(
206 codec_ctx.get(), avcodec_close);
211 unique_ptr<SwsContext, decltype(sws_freeContext)*> sws_ctx(nullptr, sws_freeContext);
212 int sws_last_width = -1, sws_last_height = -1;
215 while (!producer_thread_should_quit.should_quit()) {
216 // Process any queued commands from other threads.
217 vector<QueuedCommand> commands;
219 lock_guard<mutex> lock(queue_mu);
220 swap(commands, command_queue);
222 for (const QueuedCommand &cmd : commands) {
223 switch (cmd.command) {
224 case QueuedCommand::REWIND:
225 if (av_seek_frame(format_ctx.get(), /*stream_index=*/-1, /*timestamp=*/0, /*flags=*/0) < 0) {
226 fprintf(stderr, "%s: Rewind failed, stopping play.\n", pathname.c_str());
228 // If the file has changed since last time, return to get it reloaded.
229 // Note that depending on how you move the file into place, you might
230 // end up corrupting the one you're already playing, so this path
231 // might not trigger.
232 if (changed_since(pathname, last_modified)) {
238 case QueuedCommand::CHANGE_RATE:
239 start = next_frame_start;
240 pts_origin = last_pts;
246 // Read packets until we have a frame or there are none left.
247 int frame_finished = 0;
248 AVFrameWithDeleter frame = av_frame_alloc_unique();
252 unique_ptr<AVPacket, decltype(av_packet_unref)*> pkt_cleanup(
253 &pkt, av_packet_unref);
254 av_init_packet(&pkt);
257 if (av_read_frame(format_ctx.get(), &pkt) == 0) {
258 if (pkt.stream_index != video_stream_index) {
259 // Ignore audio for now.
262 if (avcodec_send_packet(codec_ctx.get(), &pkt) < 0) {
263 fprintf(stderr, "%s: Cannot send packet to codec.\n", pathname.c_str());
267 eof = true; // Or error, but ignore that for the time being.
270 int err = avcodec_receive_frame(codec_ctx.get(), frame.get());
272 frame_finished = true;
274 } else if (err != AVERROR(EAGAIN)) {
275 fprintf(stderr, "%s: Cannot receive frame from codec.\n", pathname.c_str());
280 if (!frame_finished) {
281 // EOF. Loop back to the start if we can.
282 if (av_seek_frame(format_ctx.get(), /*stream_index=*/-1, /*timestamp=*/0, /*flags=*/0) < 0) {
283 fprintf(stderr, "%s: Rewind failed, not looping.\n", pathname.c_str());
286 // If the file has changed since last time, return to get it reloaded.
287 // Note that depending on how you move the file into place, you might
288 // end up corrupting the one you're already playing, so this path
289 // might not trigger.
290 if (changed_since(pathname, last_modified)) {
297 if (sws_ctx == nullptr || sws_last_width != frame->width || sws_last_height != frame->height) {
299 sws_getContext(frame->width, frame->height, (AVPixelFormat)frame->format,
300 width, height, AV_PIX_FMT_BGRA,
301 SWS_BICUBIC, nullptr, nullptr, nullptr));
302 sws_last_width = frame->width;
303 sws_last_height = frame->height;
305 if (sws_ctx == nullptr) {
306 fprintf(stderr, "%s: Could not create scaler context\n", pathname.c_str());
310 VideoFormat video_format;
311 video_format.width = width;
312 video_format.height = height;
313 video_format.stride = width * 4;
314 video_format.frame_rate_nom = video_timebase.den;
315 video_format.frame_rate_den = av_frame_get_pkt_duration(frame.get()) * video_timebase.num;
316 if (video_format.frame_rate_nom == 0 || video_format.frame_rate_den == 0) {
317 // Invalid frame rate.
318 video_format.frame_rate_nom = 60;
319 video_format.frame_rate_den = 1;
321 video_format.has_signal = true;
322 video_format.is_connected = true;
324 next_frame_start = compute_frame_start(frame->pts, pts_origin, video_timebase, start, rate);
325 last_pts = frame->pts;
327 FrameAllocator::Frame video_frame = video_frame_allocator->alloc_frame();
328 if (video_frame.data != nullptr) {
329 uint8_t *pic_data[4] = { video_frame.data, nullptr, nullptr, nullptr };
330 int linesizes[4] = { int(video_format.stride), 0, 0, 0 };
331 sws_scale(sws_ctx.get(), frame->data, frame->linesize, 0, frame->height, pic_data, linesizes);
332 video_frame.len = video_format.stride * height;
333 video_frame.received_timestamp = next_frame_start;
336 FrameAllocator::Frame audio_frame;
337 AudioFormat audio_format;
338 audio_format.bits_per_sample = 32;
339 audio_format.num_channels = 8;
341 producer_thread_should_quit.sleep_until(next_frame_start);
342 frame_callback(timecode++,
343 video_frame, 0, video_format,
344 audio_frame, 0, audio_format);
349 void FFmpegCapture::internal_rewind()
351 pts_origin = last_pts = 0;
352 start = next_frame_start = steady_clock::now();