Initial community commit

Src/mp3-mpg123/mkv_mp3_decoder.cpp

@@ -0,0 +1,169 @@
+#include "mkv_mp3_decoder.h"
+#include "../nsutil/pcm.h"
+
+int MKVDecoder::CreateAudioDecoder(const char *codec_id, const nsmkv::TrackEntryData *track_entry_data, const nsmkv::AudioData *audio_data, unsigned int preferred_bits, unsigned int max_channels,bool floating_point, ifc_mkvaudiodecoder **decoder)
+{
+	if (!strcmp(codec_id, "A_MPEG/L3")
+		|| !strcmp(codec_id, "A_MPEG/L2")
+		|| !strcmp(codec_id, "A_MPEG/L1"))
+	{
+		mpg123_handle *ctx = mpg123_new(NULL, NULL);
+		if (!ctx)
+			return CREATEDECODER_FAILURE;
+
+		long flags = MPG123_QUIET|MPG123_FORCE_FLOAT|MPG123_SKIP_ID3V2|MPG123_IGNORE_STREAMLENGTH|MPG123_IGNORE_INFOFRAME;
+		if (max_channels == 1) {
+			flags |= MPG123_FORCE_MONO;
+		}
+		mpg123_param(ctx, MPG123_FLAGS, flags, 0);
+		mpg123_param(ctx, MPG123_RVA, MPG123_RVA_OFF, 0);
+
+		*decoder = new MKVMP3Decoder(ctx, preferred_bits, max_channels, floating_point);
+		return CREATEDECODER_SUCCESS;
+	}
+
+	return CREATEDECODER_NOT_MINE;
+}
+
+#define CBCLASS MKVDecoder
+START_DISPATCH;
+CB(CREATE_AUDIO_DECODER, CreateAudioDecoder)
+END_DISPATCH;
+#undef CBCLASS
+
+#define FHG_DELAY 529
+MKVMP3Decoder::MKVMP3Decoder(mpg123_handle *mp3, unsigned int bps, unsigned max_channels, bool floating_point)
+: mp3(mp3), bits(bps?bps:16), max_channels(max_channels?max_channels:2), floating_point(floating_point)
+{
+	decode_buffer=0;
+	decode_buffer_length=0;
+	sample_rate = 0;
+	channels = 0;
+	pregap = FHG_DELAY;
+	mpg123_open_feed(mp3);
+}
+
+MKVMP3Decoder::~MKVMP3Decoder()
+{
+	if (mp3) {
+		mpg123_delete(mp3);
+		mp3 = 0;
+	}
+	free(decode_buffer);
+}
+
+bool MKVMP3Decoder::_UpdateProperties()
+{
+	if (mp3 && (!channels || !sample_rate)) {
+		long sample_rate = 44100;
+		int channels = 2;
+		int encoding = 0;
+		if (mpg123_getformat(mp3, &sample_rate, &channels, &encoding) == MPG123_OK) {
+			this->channels = channels;
+			this->sample_rate = sample_rate;
+		}
+	}
+
+	return channels && sample_rate;
+}
+
+int MKVMP3Decoder::OutputFrameSize(size_t *frame_size)
+{
+	if (_UpdateProperties()) {
+		*frame_size = (bits/8) * channels * mpg123_spf(mp3);
+		return MKV_SUCCESS;
+	} else {
+		return MKV_FAILURE;
+	}
+}
+
+int MKVMP3Decoder::GetOutputProperties(unsigned int *sampleRate, unsigned int *channels, unsigned int *bitsPerSample, bool *isFloat)
+{
+	if (_UpdateProperties()) {
+		*sampleRate = this->sample_rate;
+		*channels = this->channels;
+		*bitsPerSample = bits;
+		*isFloat = floating_point;
+		return MKV_SUCCESS;
+	}
+	else
+	{
+		return MKV_FAILURE;
+	}
+}
+
+int MKVMP3Decoder::DecodeBlock(void *inputBuffer, size_t inputBufferBytes, void *outputBuffer, size_t *outputBufferBytes)
+{
+	if (!mp3)
+		return MKV_FAILURE;
+
+	*outputBufferBytes = 0;
+	mpg123_feed(mp3, (unsigned char *)inputBuffer, inputBufferBytes);
+
+	for (;;) {
+		if (!decode_buffer) {
+			if (_UpdateProperties()) {
+				decode_buffer_length = sizeof(float) * channels * mpg123_spf(mp3);
+				decode_buffer = (float *)malloc(decode_buffer_length);
+				if (!decode_buffer) {
+					return MKV_FAILURE;
+				}
+			}
+		}
+		// get the decoded data out
+		size_t pcm_buf_used=0;
+		int err = mpg123_read(mp3, (unsigned char *)decode_buffer, decode_buffer_length, &pcm_buf_used);
+
+		if (pcm_buf_used) {
+			if (!_UpdateProperties()) {
+				return MKV_FAILURE;
+			}
+			// deal with pregap
+			size_t numSamples = pcm_buf_used / sizeof(float);
+			size_t offset = min(numSamples, pregap * channels);
+			numSamples -= offset;
+			pregap -= (int)offset / channels;
+			float *pcm_buf = decode_buffer + offset;
+
+			// convert to destination sample format
+			
+			nsutil_pcm_FloatToInt_Interleaved(outputBuffer, pcm_buf, bits, numSamples);
+
+			*outputBufferBytes += numSamples * bits / 8;
+			outputBuffer = (char *)outputBuffer + numSamples * bits / 8;
+
+			return MKV_SUCCESS;
+		} else if (err == MPG123_NEED_MORE) {
+			*outputBufferBytes = 0;
+			return MKV_NEED_MORE_INPUT;
+		} else if (err == MPG123_NEW_FORMAT) {
+			continue;
+		} else if (err == MPG123_OK) {
+			continue;
+		}
+		else
+			return MKV_FAILURE;
+	}
+	return MKV_SUCCESS;
+}
+
+void MKVMP3Decoder::Flush()
+{
+	mpg123_open_feed(mp3);
+	pregap = FHG_DELAY;
+}
+
+void MKVMP3Decoder::Close()
+{
+	delete this;
+}
+
+#define CBCLASS MKVMP3Decoder
+START_DISPATCH;
+CB(OUTPUT_FRAME_SIZE, OutputFrameSize)
+CB(GET_OUTPUT_PROPERTIES, GetOutputProperties)
+CB(DECODE_BLOCK, DecodeBlock)
+VCB(FLUSH, Flush)
+VCB(CLOSE, Close)
+END_DISPATCH;
+#undef CBCLASS