Merge tag 'v0.22.11'

release v0.22.11

src/lib/ffmpeg/ChannelLayout.hxx

@@ -0,0 +1,66 @@
+/*
+ * Copyright 2003-2021 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef MPD_FFMPEG_CHANNEL_LAYOUT_HXX
+#define MPD_FFMPEG_CHANNEL_LAYOUT_HXX
+
+extern "C" {
+#include <libavutil/channel_layout.h>
+}
+
+/**
+ * Convert a MPD channel count to a libavutil channel_layout bit mask.
+ */
+static constexpr uint64_t
+ToFfmpegChannelLayout(unsigned channels) noexcept
+{
+	switch (channels) {
+	case 1:
+		return AV_CH_LAYOUT_MONO;
+
+	case 2:
+		return AV_CH_LAYOUT_STEREO;
+
+	case 3:
+		return AV_CH_LAYOUT_SURROUND;
+
+	case 4:
+		// TODO is this AV_CH_LAYOUT_2_2?
+		return AV_CH_LAYOUT_QUAD;
+
+	case 5:
+		// TODO is this AV_CH_LAYOUT_5POINT0_BACK?
+		return AV_CH_LAYOUT_5POINT0;
+
+	case 6:
+		return AV_CH_LAYOUT_5POINT1;
+
+	case 7:
+		return AV_CH_LAYOUT_6POINT1;
+
+	case 8:
+		return AV_CH_LAYOUT_7POINT1;
+
+	default:
+		/* unreachable */
+		return 0;
+	}
+}
+
+#endif

src/lib/ffmpeg/DetectFilterFormat.cxx

@@ -62,8 +62,14 @@ DetectFilterOutputFormat(const AudioFormat &in_audio_format,
 	frame.Unref();
 
 	err = av_buffersink_get_frame(&buffer_sink, frame.get());
-	if (err < 0)
+	if (err < 0) {
+		if (err == AVERROR(EAGAIN))
+			/* one sample was not enough input data for
+			   the given filter graph */
+			return AudioFormat::Undefined();
+
 		throw MakeFfmpegError(err, "av_buffersink_get_frame() failed");
+	}
 
 	const SampleFormat sample_format = FromFfmpegSampleFormat(AVSampleFormat(frame->format));
 	if (sample_format == SampleFormat::UNDEFINED)

src/lib/ffmpeg/DetectFilterFormat.hxx

@@ -35,6 +35,9 @@ namespace Ffmpeg {
  * between.
  *
  * This function can throw if the FFmpeg filter fails.
+ *
+ * @return the output format or AudioFormat::Undefined() if it was not
+ * possible to determine the format
  */
 AudioFormat
 DetectFilterOutputFormat(const AudioFormat &in_audio_format,

src/lib/ffmpeg/Filter.cxx

@@ -18,10 +18,13 @@
  */
 
 #include "Filter.hxx"
+#include "ChannelLayout.hxx"
 #include "SampleFormat.hxx"
 #include "pcm/AudioFormat.hxx"
 #include "util/RuntimeError.hxx"
 
+#include <cinttypes>
+
 #include <stdio.h>
 
 namespace Ffmpeg {
@@ -36,9 +39,32 @@ RequireFilterByName(const char *name)
 	return *filter;
 }
 
-FilterContext
-FilterContext::MakeAudioBufferSource(AudioFormat &audio_format,
-				     AVFilterGraph &graph_ctx)
+static AVFilterContext &
+CreateFilter(const AVFilter &filt,
+	     const char *name, const char *args, void *opaque,
+	     AVFilterGraph &graph_ctx)
+{
+	AVFilterContext *context = nullptr;
+	int err = avfilter_graph_create_filter(&context, &filt,
+					       name, args, opaque,
+					       &graph_ctx);
+	if (err < 0)
+		throw MakeFfmpegError(err, "avfilter_graph_create_filter() failed");
+
+	return *context;
+}
+
+static AVFilterContext &
+CreateFilter(const AVFilter &filt,
+	     const char *name,
+	     AVFilterGraph &graph_ctx)
+{
+	return CreateFilter(filt, name, nullptr, nullptr, graph_ctx);
+}
+
+AVFilterContext &
+MakeAudioBufferSource(AudioFormat &audio_format,
+		      AVFilterGraph &graph_ctx)
 {
 	AVSampleFormat src_format = ToFfmpegSampleFormat(audio_format.format);
 	if (src_format == AV_SAMPLE_FMT_NONE) {
@@ -57,19 +83,72 @@ FilterContext::MakeAudioBufferSource(AudioFormat &audio_format,
 
 	char abuffer_args[256];
 	sprintf(abuffer_args,
-		"sample_rate=%u:sample_fmt=%s:channels=%u:time_base=1/%u",
+		"sample_rate=%u:sample_fmt=%s:channel_layout=0x%" PRIx64 ":time_base=1/%u",
 		audio_format.sample_rate,
 		av_get_sample_fmt_name(src_format),
-		audio_format.channels,
+		ToFfmpegChannelLayout(audio_format.channels),
 		audio_format.sample_rate);
 
-	return {RequireFilterByName("abuffer"), "abuffer", abuffer_args, nullptr, graph_ctx};
+	return CreateFilter(RequireFilterByName("abuffer"), "abuffer",
+			    abuffer_args, nullptr, graph_ctx);
 }
 
-FilterContext
-FilterContext::MakeAudioBufferSink(AVFilterGraph &graph_ctx)
+AVFilterContext &
+MakeAudioBufferSink(AVFilterGraph &graph_ctx)
 {
-	return {RequireFilterByName("abuffersink"), "abuffersink", graph_ctx};
+	return CreateFilter(RequireFilterByName("abuffersink"), "abuffersink",
+			    graph_ctx);
+}
+
+AVFilterContext &
+MakeAformat(AudioFormat &audio_format,
+	    AVFilterGraph &graph_ctx)
+{
+	AVSampleFormat dest_format = ToFfmpegSampleFormat(audio_format.format);
+	if (dest_format == AV_SAMPLE_FMT_NONE) {
+		switch (audio_format.format) {
+		case SampleFormat::S24_P32:
+			audio_format.format = SampleFormat::S32;
+			dest_format = AV_SAMPLE_FMT_S32;
+			break;
+
+		default:
+			audio_format.format = SampleFormat::S16;
+			dest_format = AV_SAMPLE_FMT_S16;
+			break;
+		}
+	}
+
+	char args[256];
+	sprintf(args,
+		"sample_rates=%u:sample_fmts=%s:channel_layouts=0x%" PRIx64,
+		audio_format.sample_rate,
+		av_get_sample_fmt_name(dest_format),
+		ToFfmpegChannelLayout(audio_format.channels));
+
+	return CreateFilter(RequireFilterByName("aformat"), "aformat",
+			    args, nullptr, graph_ctx);
+}
+
+AVFilterContext &
+MakeAutoAformat(AVFilterGraph &graph_ctx)
+{
+	return CreateFilter(RequireFilterByName("aformat"), "aformat",
+			    "sample_fmts=flt|s32|s16",
+			    nullptr, graph_ctx);
+}
+
+void
+FilterGraph::ParseSingleInOut(const char *filters, AVFilterContext &in,
+			      AVFilterContext &out)
+{
+	auto [inputs, outputs] = Parse(filters, {"out", in}, {"in", out});
+
+	if (inputs.get() != nullptr)
+		throw std::runtime_error("FFmpeg filter has an open input");
+
+	if (outputs.get() != nullptr)
+		throw std::runtime_error("FFmpeg filter has an open output");
 }
 
 } // namespace Ffmpeg

src/lib/ffmpeg/Filter.hxx

@@ -77,63 +77,38 @@ public:
 	}
 };
 
-class FilterContext {
-	AVFilterContext *context = nullptr;
+/**
+ * Create an "abuffer" filter.
+ *
+ * @param the input audio format; may be modified by the
+ * function to ask the caller to do format conversion
+ */
+AVFilterContext &
+MakeAudioBufferSource(AudioFormat &audio_format,
+		      AVFilterGraph &graph_ctx);
 
-public:
-	FilterContext() = default;
+/**
+ * Create an "abuffersink" filter.
+ */
+AVFilterContext &
+MakeAudioBufferSink(AVFilterGraph &graph_ctx);
 
-	FilterContext(const AVFilter &filt,
-		      const char *name, const char *args, void *opaque,
-		      AVFilterGraph &graph_ctx) {
-		int err = avfilter_graph_create_filter(&context, &filt,
-						       name, args, opaque,
-						       &graph_ctx);
-		if (err < 0)
-			throw MakeFfmpegError(err, "avfilter_graph_create_filter() failed");
-	}
+/**
+ * Create an "aformat" filter.
+ *
+ * @param the output audio format; may be modified by the function if
+ * the given format is not supported by libavfilter
+ */
+AVFilterContext &
+MakeAformat(AudioFormat &audio_format,
+	    AVFilterGraph &graph_ctx);
 
-	FilterContext(const AVFilter &filt,
-		      const char *name,
-		      AVFilterGraph &graph_ctx)
-		:FilterContext(filt, name, nullptr, nullptr, graph_ctx) {}
-
-	FilterContext(FilterContext &&src) noexcept
-		:context(std::exchange(src.context, nullptr)) {}
-
-	~FilterContext() noexcept {
-		if (context != nullptr)
-			avfilter_free(context);
-	}
-
-	FilterContext &operator=(FilterContext &&src) noexcept {
-		using std::swap;
-		swap(context, src.context);
-		return *this;
-	}
-
-	/**
-	 * Create an "abuffer" filter.
-	 *
-	 * @param the input audio format; may be modified by the
-	 * function to ask the caller to do format conversion
-	 */
-	static FilterContext MakeAudioBufferSource(AudioFormat &audio_format,
-						   AVFilterGraph &graph_ctx);
-
-	/**
-	 * Create an "abuffersink" filter.
-	 */
-	static FilterContext MakeAudioBufferSink(AVFilterGraph &graph_ctx);
-
-	auto &operator*() noexcept {
-		return *context;
-	}
-
-	auto *get() noexcept {
-		return context;
-	}
-};
+/**
+ * Create an "aformat" filter which automatically converts the output
+ * to a format supported by MPD.
+ */
+AVFilterContext &
+MakeAutoAformat(AVFilterGraph &graph_ctx);
 
 class FilterGraph {
 	AVFilterGraph *graph = nullptr;
@@ -180,6 +155,9 @@ public:
 		return std::make_pair(std::move(inputs), std::move(outputs));
 	}
 
+	void ParseSingleInOut(const char *filters, AVFilterContext &in,
+			      AVFilterContext &out);
+
 	std::pair<FilterInOut, FilterInOut> Parse(const char *filters) {
 		AVFilterInOut *inputs, *outputs;
 		int err = avfilter_graph_parse2(graph, filters,