X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=ffmpeg_capture.cpp;h=fb1b223c326f4e789193da4e078c65a48d729ec5;hb=96cb6414f85e0ef4d660b7bd56267303e80fcd05;hp=bb41a35a4dc01b9909cb374967c65a0153216179;hpb=321995944e46e187ee515d358f137d94c30f090e;p=nageru diff --git a/ffmpeg_capture.cpp b/ffmpeg_capture.cpp index bb41a35..fb1b223 100644 --- a/ffmpeg_capture.cpp +++ b/ffmpeg_capture.cpp @@ -6,6 +6,7 @@ #include #include #include +#include #include extern "C" { @@ -27,6 +28,7 @@ extern "C" { #include "bmusb/bmusb.h" #include "ffmpeg_raii.h" +#include "ffmpeg_util.h" #include "flags.h" #include "image_input.h" @@ -35,12 +37,175 @@ extern "C" { using namespace std; using namespace std::chrono; using namespace bmusb; +using namespace movit; + +namespace { + +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) +{ + const duration pts((frame_pts - pts_origin) * double(video_timebase.num) / double(video_timebase.den)); + return origin + duration_cast(pts / rate); +} + +bool changed_since(const std::string &pathname, const timespec &ts) +{ + if (ts.tv_sec < 0) { + return false; + } + struct stat buf; + if (stat(pathname.c_str(), &buf) != 0) { + fprintf(stderr, "%s: Couldn't check for new version, leaving the old in place.\n", pathname.c_str()); + return false; + } + return (buf.st_mtim.tv_sec != ts.tv_sec || buf.st_mtim.tv_nsec != ts.tv_nsec); +} + +bool is_full_range(const AVPixFmtDescriptor *desc) +{ + // This is horrible, but there's no better way that I know of. + return (strchr(desc->name, 'j') != nullptr); +} + +AVPixelFormat decide_dst_format(AVPixelFormat src_format, bmusb::PixelFormat dst_format_type) +{ + if (dst_format_type == bmusb::PixelFormat_8BitBGRA) { + return AV_PIX_FMT_BGRA; + } + + assert(dst_format_type == bmusb::PixelFormat_8BitYCbCrPlanar); + + // If this is a non-Y'CbCr format, just convert to 4:4:4 Y'CbCr + // and be done with it. It's too strange to spend a lot of time on. + // (Let's hope there's no alpha.) + const AVPixFmtDescriptor *src_desc = av_pix_fmt_desc_get(src_format); + if (src_desc == nullptr || + src_desc->nb_components != 3 || + (src_desc->flags & AV_PIX_FMT_FLAG_RGB)) { + return AV_PIX_FMT_YUV444P; + } + + // The best for us would be Cb and Cr together if possible, + // but FFmpeg doesn't support that except in the special case of + // NV12, so we need to go to planar even for the case of NV12. + // Thus, look for the closest (but no worse) 8-bit planar Y'CbCr format + // that matches in color range. (This will also include the case of + // the source format already being acceptable.) + bool src_full_range = is_full_range(src_desc); + const char *best_format = "yuv444p"; + unsigned best_score = numeric_limits::max(); + for (const AVPixFmtDescriptor *desc = av_pix_fmt_desc_next(nullptr); + desc; + desc = av_pix_fmt_desc_next(desc)) { + // Find planar Y'CbCr formats only. + if (desc->nb_components != 3) continue; + if (desc->flags & AV_PIX_FMT_FLAG_RGB) continue; + if (!(desc->flags & AV_PIX_FMT_FLAG_PLANAR)) continue; + if (desc->comp[0].plane != 0 || + desc->comp[1].plane != 1 || + desc->comp[2].plane != 2) continue; + + // 8-bit formats only. + if (desc->flags & AV_PIX_FMT_FLAG_BE) continue; + if (desc->comp[0].depth != 8) continue; + + // Same or better chroma resolution only. + int chroma_w_diff = desc->log2_chroma_w - src_desc->log2_chroma_w; + int chroma_h_diff = desc->log2_chroma_h - src_desc->log2_chroma_h; + if (chroma_w_diff < 0 || chroma_h_diff < 0) + continue; + + // Matching full/limited range only. + if (is_full_range(desc) != src_full_range) + continue; + + // Pick something with as little excess chroma resolution as possible. + unsigned score = (1 << (chroma_w_diff)) << chroma_h_diff; + if (score < best_score) { + best_score = score; + best_format = desc->name; + } + } + return av_get_pix_fmt(best_format); +} + +YCbCrFormat decode_ycbcr_format(const AVPixFmtDescriptor *desc, const AVFrame *frame) +{ + YCbCrFormat format; + AVColorSpace colorspace = av_frame_get_colorspace(frame); + switch (colorspace) { + case AVCOL_SPC_BT709: + format.luma_coefficients = YCBCR_REC_709; + break; + case AVCOL_SPC_BT470BG: + case AVCOL_SPC_SMPTE170M: + case AVCOL_SPC_SMPTE240M: + format.luma_coefficients = YCBCR_REC_601; + break; + case AVCOL_SPC_BT2020_NCL: + format.luma_coefficients = YCBCR_REC_2020; + break; + case AVCOL_SPC_UNSPECIFIED: + format.luma_coefficients = (frame->height >= 720 ? YCBCR_REC_709 : YCBCR_REC_601); + break; + default: + fprintf(stderr, "Unknown Y'CbCr coefficient enum %d from FFmpeg; choosing Rec. 709.\n", + colorspace); + format.luma_coefficients = YCBCR_REC_709; + break; + } + + format.full_range = is_full_range(desc); + format.num_levels = 1 << desc->comp[0].depth; + format.chroma_subsampling_x = 1 << desc->log2_chroma_w; + format.chroma_subsampling_y = 1 << desc->log2_chroma_h; + + switch (frame->chroma_location) { + case AVCHROMA_LOC_LEFT: + format.cb_x_position = 0.0; + format.cb_y_position = 0.5; + break; + case AVCHROMA_LOC_CENTER: + format.cb_x_position = 0.5; + format.cb_y_position = 0.5; + break; + case AVCHROMA_LOC_TOPLEFT: + format.cb_x_position = 0.0; + format.cb_y_position = 0.0; + break; + case AVCHROMA_LOC_TOP: + format.cb_x_position = 0.5; + format.cb_y_position = 0.0; + break; + case AVCHROMA_LOC_BOTTOMLEFT: + format.cb_x_position = 0.0; + format.cb_y_position = 1.0; + break; + case AVCHROMA_LOC_BOTTOM: + format.cb_x_position = 0.5; + format.cb_y_position = 1.0; + break; + default: + fprintf(stderr, "Unknown chroma location coefficient enum %d from FFmpeg; choosing Rec. 709.\n", + frame->chroma_location); + format.cb_x_position = 0.5; + format.cb_y_position = 0.5; + break; + } + + format.cr_x_position = format.cb_x_position; + format.cr_y_position = format.cb_y_position; + return format; +} + +} // namespace FFmpegCapture::FFmpegCapture(const string &filename, unsigned width, unsigned height) - : filename(filename), width(width), height(height) + : filename(filename), width(width), height(height), video_timebase{1, 1} { // Not really used for anything. description = "Video: " + filename; + + avformat_network_init(); // In case someone wants this. } FFmpegCapture::~FFmpegCapture() @@ -68,7 +233,7 @@ void FFmpegCapture::start_bm_capture() return; } running = true; - producer_thread_should_quit = false; + producer_thread_should_quit.unquit(); producer_thread = thread(&FFmpegCapture::producer_thread_func, this); } @@ -78,7 +243,7 @@ void FFmpegCapture::stop_dequeue_thread() return; } running = false; - producer_thread_should_quit = true; + producer_thread_should_quit.quit(); producer_thread.join(); } @@ -107,17 +272,19 @@ void FFmpegCapture::producer_thread_func() snprintf(thread_name, sizeof(thread_name), "FFmpeg_C_%d", card_index); pthread_setname_np(pthread_self(), thread_name); - while (!producer_thread_should_quit) { + 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()); - sleep(1); + send_disconnected_frame(); + producer_thread_should_quit.sleep_for(seconds(1)); continue; } if (!play_video(pathname)) { // Error. fprintf(stderr, "Error when playing %s, sleeping one second and trying again...\n", pathname.c_str()); - sleep(1); + send_disconnected_frame(); + producer_thread_should_quit.sleep_for(seconds(1)); continue; } @@ -130,8 +297,42 @@ void FFmpegCapture::producer_thread_func() } } +void FFmpegCapture::send_disconnected_frame() +{ + // Send an empty frame to signal that we have no signal anymore. + FrameAllocator::Frame video_frame = video_frame_allocator->alloc_frame(); + if (video_frame.data) { + 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); + + frame_callback(timecode++, + video_frame, /*video_offset=*/0, video_format, + FrameAllocator::Frame(), /*audio_offset=*/0, AudioFormat()); + } +} + bool FFmpegCapture::play_video(const string &pathname) { + // Note: Call before open, not after; otherwise, there's a race. + // (There is now, too, but it tips the correct way. We could use fstat() + // if we had the file descriptor.) + timespec last_modified; + struct stat buf; + if (stat(pathname.c_str(), &buf) != 0) { + // Probably some sort of protocol, so can't stat. + last_modified.tv_sec = -1; + } else { + last_modified = buf.st_mtim; + } + auto format_ctx = avformat_open_input_unique(pathname.c_str(), nullptr, nullptr); if (format_ctx == nullptr) { fprintf(stderr, "%s: Error opening file\n", pathname.c_str()); @@ -143,25 +344,14 @@ bool FFmpegCapture::play_video(const string &pathname) return false; } - int video_stream_index = -1, audio_stream_index = -1; - AVRational video_timebase{ 1, 1 }; - for (unsigned i = 0; i < format_ctx->nb_streams; ++i) { - if (format_ctx->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO && - video_stream_index == -1) { - video_stream_index = i; - video_timebase = format_ctx->streams[i]->time_base; - } - if (format_ctx->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_AUDIO && - audio_stream_index == -1) { - audio_stream_index = i; - } - } + int video_stream_index = find_stream_index(format_ctx.get(), AVMEDIA_TYPE_VIDEO); if (video_stream_index == -1) { fprintf(stderr, "%s: No video stream found\n", pathname.c_str()); return false; } const AVCodecParameters *codecpar = format_ctx->streams[video_stream_index]->codecpar; + video_timebase = format_ctx->streams[video_stream_index]->time_base; AVCodecContextWithDeleter codec_ctx = avcodec_alloc_context3_unique(nullptr); if (avcodec_parameters_to_context(codec_ctx.get(), codecpar) < 0) { fprintf(stderr, "%s: Cannot fill codec parameters\n", pathname.c_str()); @@ -179,116 +369,252 @@ bool FFmpegCapture::play_video(const string &pathname) unique_ptr codec_ctx_cleanup( codec_ctx.get(), avcodec_close); - steady_clock::time_point start = steady_clock::now(); - - unique_ptr sws_ctx(nullptr, sws_freeContext); - int sws_last_width = -1, sws_last_height = -1; + internal_rewind(); // Main loop. - while (!producer_thread_should_quit) { - // Process any queued commands from other threads. - vector commands; - { - lock_guard lock(queue_mu); - swap(commands, command_queue); - } - for (const QueuedCommand &cmd : commands) { - if (cmd.command == QueuedCommand::REWIND) { - if (av_seek_frame(format_ctx.get(), /*stream_index=*/-1, /*timestamp=*/0, /*flags=*/0) < 0) { - fprintf(stderr, "%s: Rewind failed, stopping play.\n", pathname.c_str()); - } - start = steady_clock::now(); - continue; - } + while (!producer_thread_should_quit.should_quit()) { + if (process_queued_commands(format_ctx.get(), pathname, last_modified, /*rewound=*/nullptr)) { + return true; } - // Read packets until we have a frame or there are none left. - int frame_finished = 0; - AVFrameWithDeleter frame = av_frame_alloc_unique(); - bool eof = false; - do { - AVPacket pkt; - unique_ptr pkt_cleanup( - &pkt, av_packet_unref); - av_init_packet(&pkt); - pkt.data = nullptr; - pkt.size = 0; - if (av_read_frame(format_ctx.get(), &pkt) == 0) { - if (pkt.stream_index != video_stream_index) { - // Ignore audio for now. - continue; - } - if (avcodec_send_packet(codec_ctx.get(), &pkt) < 0) { - fprintf(stderr, "%s: Cannot send packet to codec.\n", pathname.c_str()); - return false; - } - } else { - eof = true; // Or error, but ignore that for the time being. - } - - int err = avcodec_receive_frame(codec_ctx.get(), frame.get()); - if (err == 0) { - frame_finished = true; - break; - } else if (err != AVERROR(EAGAIN)) { - fprintf(stderr, "%s: Cannot receive frame from codec.\n", pathname.c_str()); - return false; - } - } while (!eof); - - if (!frame_finished) { + bool error; + AVFrameWithDeleter frame = decode_frame(format_ctx.get(), codec_ctx.get(), pathname, video_stream_index, &error); + if (error) { + return false; + } + if (frame == nullptr) { // EOF. Loop back to the start if we can. if (av_seek_frame(format_ctx.get(), /*stream_index=*/-1, /*timestamp=*/0, /*flags=*/0) < 0) { fprintf(stderr, "%s: Rewind failed, not looping.\n", pathname.c_str()); return true; } - start = steady_clock::now(); + // 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 + // might not trigger. + if (changed_since(pathname, last_modified)) { + return true; + } + internal_rewind(); continue; } - if (sws_ctx == nullptr || sws_last_width != frame->width || sws_last_height != frame->height) { - sws_ctx.reset( - sws_getContext(frame->width, frame->height, (AVPixelFormat)frame->format, - width, height, AV_PIX_FMT_RGBA, - SWS_BICUBIC, nullptr, nullptr, nullptr)); - sws_last_width = frame->width; - sws_last_height = frame->height; - } - if (sws_ctx == nullptr) { - fprintf(stderr, "%s: Could not create scaler context\n", pathname.c_str()); + VideoFormat video_format = construct_video_format(frame.get(), video_timebase); + FrameAllocator::Frame video_frame = make_video_frame(frame.get(), pathname, &error); + if (error) { return false; } - VideoFormat video_format; - video_format.width = width; - video_format.height = height; - video_format.stride = width * 4; - video_format.frame_rate_nom = video_timebase.den; - video_format.frame_rate_den = av_frame_get_pkt_duration(frame.get()) * video_timebase.num; - video_format.has_signal = true; - video_format.is_connected = true; - - const duration pts(frame->pts * double(video_timebase.num) / double(video_timebase.den)); - const steady_clock::time_point frame_start = start + duration_cast(pts); - - FrameAllocator::Frame video_frame = video_frame_allocator->alloc_frame(); - if (video_frame.data != nullptr) { - uint8_t *pic_data[4] = { video_frame.data, nullptr, nullptr, nullptr }; - int linesizes[4] = { int(video_format.stride), 0, 0, 0 }; - sws_scale(sws_ctx.get(), frame->data, frame->linesize, 0, frame->height, pic_data, linesizes); - video_frame.len = video_format.stride * height; - video_frame.received_timestamp = frame_start; - } - FrameAllocator::Frame audio_frame; AudioFormat audio_format; audio_format.bits_per_sample = 32; audio_format.num_channels = 8; - this_thread::sleep_until(frame_start); - frame_callback(timecode++, - video_frame, 0, video_format, - audio_frame, 0, audio_format); + for ( ;; ) { + next_frame_start = compute_frame_start(frame->pts, pts_origin, video_timebase, start, rate); + video_frame.received_timestamp = next_frame_start; + bool finished_wakeup = producer_thread_should_quit.sleep_until(next_frame_start); + if (finished_wakeup) { + frame_callback(timecode++, + video_frame, 0, video_format, + audio_frame, 0, audio_format); + break; + } else { + if (producer_thread_should_quit.should_quit()) break; + + bool rewound = false; + if (process_queued_commands(format_ctx.get(), pathname, last_modified, &rewound)) { + return true; + } + // 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, + // but if it's now in the past, we'll reset the origin, so that we don't + // generate a huge backlog of frames that we need to run through quickly. + next_frame_start = compute_frame_start(frame->pts, pts_origin, video_timebase, start, rate); + steady_clock::time_point now = steady_clock::now(); + if (next_frame_start < now) { + pts_origin = frame->pts; + start = next_frame_start = now; + } + } + } + last_pts = frame->pts; } return true; } + +void FFmpegCapture::internal_rewind() +{ + pts_origin = last_pts = 0; + start = next_frame_start = steady_clock::now(); +} + +bool FFmpegCapture::process_queued_commands(AVFormatContext *format_ctx, const std::string &pathname, timespec last_modified, bool *rewound) +{ + // Process any queued commands from other threads. + vector commands; + { + lock_guard lock(queue_mu); + swap(commands, command_queue); + } + for (const QueuedCommand &cmd : commands) { + switch (cmd.command) { + case QueuedCommand::REWIND: + if (av_seek_frame(format_ctx, /*stream_index=*/-1, /*timestamp=*/0, /*flags=*/0) < 0) { + fprintf(stderr, "%s: Rewind failed, stopping play.\n", pathname.c_str()); + } + // 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 + // might not trigger. + if (changed_since(pathname, last_modified)) { + return true; + } + internal_rewind(); + if (rewound != nullptr) { + *rewound = true; + } + break; + + case QueuedCommand::CHANGE_RATE: + // Change the origin to the last played frame. + start = compute_frame_start(last_pts, pts_origin, video_timebase, start, rate); + pts_origin = last_pts; + rate = cmd.new_rate; + break; + } + } + return false; +} + +AVFrameWithDeleter FFmpegCapture::decode_frame(AVFormatContext *format_ctx, AVCodecContext *codec_ctx, const std::string &pathname, int video_stream_index, bool *error) +{ + *error = false; + + // Read packets until we have a frame or there are none left. + bool frame_finished = false; + AVFrameWithDeleter frame = av_frame_alloc_unique(); + bool eof = false; + do { + AVPacket pkt; + unique_ptr pkt_cleanup( + &pkt, av_packet_unref); + av_init_packet(&pkt); + pkt.data = nullptr; + pkt.size = 0; + if (av_read_frame(format_ctx, &pkt) == 0) { + if (pkt.stream_index != video_stream_index) { + // Ignore audio for now. + continue; + } + if (avcodec_send_packet(codec_ctx, &pkt) < 0) { + fprintf(stderr, "%s: Cannot send packet to codec.\n", pathname.c_str()); + *error = true; + return AVFrameWithDeleter(nullptr); + } + } else { + eof = true; // Or error, but ignore that for the time being. + } + + int err = avcodec_receive_frame(codec_ctx, frame.get()); + if (err == 0) { + frame_finished = true; + break; + } else if (err != AVERROR(EAGAIN)) { + fprintf(stderr, "%s: Cannot receive frame from codec.\n", pathname.c_str()); + *error = true; + return AVFrameWithDeleter(nullptr); + } + } while (!eof); + + if (frame_finished) + return frame; + else + return AVFrameWithDeleter(nullptr); +} + +VideoFormat FFmpegCapture::construct_video_format(const AVFrame *frame, AVRational video_timebase) +{ + VideoFormat video_format; + video_format.width = width; + video_format.height = height; + if (pixel_format == bmusb::PixelFormat_8BitBGRA) { + video_format.stride = width * 4; + } else { + assert(pixel_format == bmusb::PixelFormat_8BitYCbCrPlanar); + video_format.stride = width; + } + video_format.frame_rate_nom = video_timebase.den; + video_format.frame_rate_den = av_frame_get_pkt_duration(frame) * video_timebase.num; + if (video_format.frame_rate_nom == 0 || video_format.frame_rate_den == 0) { + // Invalid frame rate. + video_format.frame_rate_nom = 60; + video_format.frame_rate_den = 1; + } + video_format.has_signal = true; + video_format.is_connected = true; + return video_format; +} + +FrameAllocator::Frame 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) { + return video_frame; + } + + if (sws_ctx == nullptr || + sws_last_width != frame->width || + sws_last_height != frame->height || + sws_last_src_format != frame->format) { + sws_dst_format = decide_dst_format(AVPixelFormat(frame->format), pixel_format); + sws_ctx.reset( + sws_getContext(frame->width, frame->height, AVPixelFormat(frame->format), + width, height, sws_dst_format, + SWS_BICUBIC, nullptr, nullptr, nullptr)); + sws_last_width = frame->width; + sws_last_height = frame->height; + sws_last_src_format = frame->format; + } + if (sws_ctx == nullptr) { + fprintf(stderr, "%s: Could not create scaler context\n", pathname.c_str()); + *error = true; + 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; + linesizes[0] = width * 4; + video_frame.len = (width * 4) * height; + } else { + assert(pixel_format == bmusb::PixelFormat_8BitYCbCrPlanar); + const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(sws_dst_format); + + 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; + linesizes[0] = width; + + pic_data[1] = pic_data[0] + width * height; + linesizes[1] = chroma_width; + + pic_data[2] = pic_data[1] + chroma_width * chroma_height; + linesizes[2] = chroma_width; + + video_frame.len = width * height + 2 * chroma_width * chroma_height; + + current_frame_ycbcr_format = decode_ycbcr_format(desc, frame); + } + sws_scale(sws_ctx.get(), frame->data, frame->linesize, 0, frame->height, pic_data, linesizes); + + return video_frame; +}