win-mf: Add Media Foundation AAC Encoder

Adds Microsoft Media Foundation AAC Encoder that supports 96k to 192k bitrates. This plugin is only enabled on Microsoft Windows 8+ due to performance issues found on Windows 7.
2026-10-29 19:22:36 +08:00 · 2015-07-07 23:05:44 -07:00
parent 39261b8da6
commit 3ae747dd50
8 changed files with 644 additions and 0 deletions
@@ -0,0 +1,168 @@
+#include <obs-module.h>
+
+#include <memory>
+
+#include "mf-aac-encoder.hpp"
+
+#include <VersionHelpers.h>
+
+using namespace MFAAC;
+
+static const char *MFAAC_GetName()
+{
+	return obs_module_text("MFAACEnc");
+}
+
+static obs_properties_t *MFAAC_GetProperties(void *)
+{
+	obs_properties_t *props = obs_properties_create();
+
+	obs_properties_add_int(props, "bitrate",
+			obs_module_text("Bitrate"), 96, 192, 32);
+
+	return props;
+}
+
+static void MFAAC_GetDefaults(obs_data_t *settings)
+{
+	obs_data_set_default_int(settings, "bitrate", 128);
+}
+
+static void *MFAAC_Create(obs_data_t *settings, obs_encoder_t *encoder)
+{
+	UINT32 bitrate = (UINT32)obs_data_get_int(settings, "bitrate");
+	if (!bitrate) {
+		MF_LOG_ENCODER("AAC", encoder, LOG_ERROR,
+			"Invalid bitrate specified");
+		return NULL;
+	}
+
+	audio_t *audio = obs_encoder_audio(encoder);
+	UINT32 channels = (UINT32)audio_output_get_channels(audio);
+	UINT32 sampleRate = audio_output_get_sample_rate(audio);
+	UINT32 bitsPerSample = 16;
+
+	UINT32 recommendedSampleRate = FindBestSamplerateMatch(sampleRate);
+	if (recommendedSampleRate != sampleRate) {
+		MF_LOG_ENCODER("AAC", encoder, LOG_WARNING,
+			"unsupported sample rate; "
+			"resampling to best guess '%d' instead of '%d'",
+			recommendedSampleRate, sampleRate);
+		sampleRate = recommendedSampleRate;
+	}
+
+	UINT32 recommendedBitRate = FindBestBitrateMatch(bitrate);
+	if (recommendedBitRate != bitrate) {
+		MF_LOG_ENCODER("AAC", encoder, LOG_WARNING,
+			"unsupported bitrate; "
+			"resampling to best guess '%d' instead of '%d'",
+			recommendedBitRate, bitrate);
+		bitrate = recommendedBitRate;
+	}
+
+	std::unique_ptr<Encoder> enc(new Encoder(encoder,
+			bitrate, channels, sampleRate, bitsPerSample));
+
+	audio_convert_info aci;
+	aci.samples_per_sec = sampleRate;
+
+	if (!enc->Initialize())
+		return nullptr;
+
+	return enc.release();
+}
+
+static void MFAAC_Destroy(void *data)
+{
+	Encoder *enc = static_cast<Encoder *>(data);
+	delete enc;
+}
+
+static bool MFAAC_Encode(void *data, struct encoder_frame *frame,
+		struct encoder_packet *packet, bool *received_packet)
+{
+	Encoder *enc = static_cast<Encoder *>(data);
+	Status status;
+
+	if (!enc->ProcessInput(frame->data[0], frame->linesize[0], frame->pts,
+			&status))
+		return false;
+
+	// This shouldn't happen since we drain right after
+	// we process input
+	if (status == NOT_ACCEPTING)
+		return false;
+
+	UINT8 *outputData;
+	UINT32 outputDataLength;
+	UINT64 outputPts;
+
+	if (!enc->ProcessOutput(&outputData, &outputDataLength, &outputPts,
+			&status))
+		return false;
+
+	// Needs more input, not a failure case
+	if (status == NEED_MORE_INPUT)
+		return true;
+
+	packet->pts = outputPts;
+	packet->dts = outputPts;
+	packet->data = outputData;
+	packet->size = outputDataLength;
+	packet->type = OBS_ENCODER_AUDIO;
+	packet->timebase_num = 1;
+	packet->timebase_den = enc->SampleRate();
+
+	return *received_packet = true;
+}
+
+static bool MFAAC_GetExtraData(void *data, uint8_t **extra_data, size_t *size)
+{
+	Encoder *enc = static_cast<Encoder *>(data);
+
+	UINT32 length;
+	if (enc->ExtraData(extra_data, &length)) {
+		*size = length;
+		return true;
+	}
+	return false;
+}
+
+static void MFAAC_GetAudioInfo(void *, struct audio_convert_info *info)
+{
+	info->format = AUDIO_FORMAT_16BIT;
+	info->samples_per_sec = FindBestSamplerateMatch(info->samples_per_sec);
+}
+
+static size_t MFAAC_GetFrameSize(void *)
+{
+	return Encoder::FrameSize;
+}
+
+extern "C" void RegisterMFAACEncoder()
+{
+	if (!IsWindows8OrGreater()) {
+		MF_LOG(LOG_WARNING, "plugin is disabled for performance "
+			"reasons on Windows versions less than 8");
+		return;
+	}
+
+	obs_encoder_info info = {};
+	info.id                        = "mf_aac";
+	info.type                      = OBS_ENCODER_AUDIO;
+	info.codec                     = "AAC";
+	info.get_name                  = MFAAC_GetName;
+	info.create                    = MFAAC_Create;
+	info.destroy                   = MFAAC_Destroy;
+	info.encode                    = MFAAC_Encode;
+	info.get_frame_size            = MFAAC_GetFrameSize;
+	info.get_defaults              = MFAAC_GetDefaults;
+	info.get_properties            = MFAAC_GetProperties;
+	info.get_extra_data            = MFAAC_GetExtraData;
+	info.get_audio_info            = MFAAC_GetAudioInfo;
+
+	MF_LOG(LOG_INFO, "Adding Media Foundation AAC Encoder");
+
+	obs_register_encoder(&info);
+
+}