X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=ffmpeg_capture.cpp;h=305a4d706fbcf6f70686d7439216f10c3580b3df;hb=135963becbab6b243527e283b38f1b67e8ecdcf6;hp=ab35c5c5ef1c5f18e66f338fa1cad20fef860a9d;hpb=72afc695d201f9d2a0dcb316ec62f1610db5fa74;p=nageru

diff --git a/ffmpeg_capture.cpp b/ffmpeg_capture.cpp
index ab35c5c..305a4d7 100644
--- a/ffmpeg_capture.cpp
+++ b/ffmpeg_capture.cpp
@@ -37,6 +37,7 @@ extern "C" {
 using namespace std;
 using namespace std::chrono;
 using namespace bmusb;
+using namespace movit;
 
 namespace {
 
@@ -59,6 +60,143 @@ bool changed_since(const std::string &pathname, const timespec &ts)
 	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<unsigned>::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)
@@ -66,6 +204,8 @@ FFmpegCapture::FFmpegCapture(const string &filename, unsigned width, unsigned he
 {
 	// Not really used for anything.
 	description = "Video: " + filename;
+
+	avformat_network_init();  // In case someone wants this.
 }
 
 FFmpegCapture::~FFmpegCapture()
@@ -136,12 +276,14 @@ void FFmpegCapture::producer_thread_func()
 		string pathname = search_for_file(filename);
 		if (filename.empty()) {
 			fprintf(stderr, "%s not found, sleeping one second and trying again...\n", filename.c_str());
+			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());
+			send_disconnected_frame();
 			producer_thread_should_quit.sleep_for(seconds(1));
 			continue;
 		}
@@ -155,6 +297,28 @@ 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.
@@ -206,78 +370,23 @@ bool FFmpegCapture::play_video(const string &pathname)
 		codec_ctx.get(), avcodec_close);
 
 	internal_rewind();
-	double rate = 1.0;
 
 	unique_ptr<SwsContext, decltype(sws_freeContext)*> sws_ctx(nullptr, sws_freeContext);
-	int sws_last_width = -1, sws_last_height = -1;
+	int sws_last_width = -1, sws_last_height = -1, sws_last_src_format = -1;
+	AVPixelFormat sws_dst_format = AVPixelFormat(-1);  // In practice, always initialized.
 
 	// Main loop.
 	while (!producer_thread_should_quit.should_quit()) {
-		// Process any queued commands from other threads.
-		vector<QueuedCommand> commands;
-		{
-			lock_guard<mutex> lock(queue_mu);
-			swap(commands, command_queue);
-		}
-		for (const QueuedCommand &cmd : commands) {
-			switch (cmd.command) {
-			case 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());
-				}
-				// 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();
-				break;
-
-			case QueuedCommand::CHANGE_RATE:
-				start = next_frame_start;
-				pts_origin = last_pts;
-				rate = cmd.new_rate;
-				break;
-			}
+		if (process_queued_commands(format_ctx.get(), pathname, last_modified)) {
+			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<AVPacket, decltype(av_packet_unref)*> 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());
@@ -294,13 +403,18 @@ bool FFmpegCapture::play_video(const string &pathname)
 			continue;
 		}
 
-		if (sws_ctx == nullptr || sws_last_width != frame->width || sws_last_height != frame->height) {
+		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, AV_PIX_FMT_BGRA,
+				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());
@@ -310,7 +424,12 @@ bool FFmpegCapture::play_video(const string &pathname)
 		VideoFormat video_format;
 		video_format.width = width;
 		video_format.height = height;
-		video_format.stride = width * 4;
+		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.get()) * video_timebase.num;
 		if (video_format.frame_rate_nom == 0 || video_format.frame_rate_den == 0) {
@@ -326,10 +445,33 @@ bool FFmpegCapture::play_video(const string &pathname)
 
 		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 };
+			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] = video_format.stride;
+				video_frame.len = video_format.stride * 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.get());
+			}
 			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 = next_frame_start;
 		}
 
@@ -351,3 +493,83 @@ 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)
+{
+	// Process any queued commands from other threads.
+	vector<QueuedCommand> commands;
+	{
+		lock_guard<mutex> 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();
+			break;
+
+		case QueuedCommand::CHANGE_RATE:
+			start = next_frame_start;
+			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<AVPacket, decltype(av_packet_unref)*> 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);
+}