Initial community commit

Src/mp3-mpg123/flv_mp3_decoder.cpp

@@ -0,0 +1,194 @@
+#include "flv_mp3_decoder.h"
+#include "../nsutil/pcm.h"
+
+int FLVDecoderCreator::CreateAudioDecoder(int stereo, int bits, int sample_rate, int format_type, ifc_flvaudiodecoder **decoder)
+{
+	if (format_type == FLV::AUDIO_FORMAT_MP3 || format_type == FLV::AUDIO_FORMAT_MP3_8KHZ)
+	{
+		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 (!stereo) {
+			flags |= MPG123_FORCE_MONO;
+		}
+		mpg123_param(ctx, MPG123_FLAGS, flags, 0);
+		mpg123_param(ctx, MPG123_RVA, MPG123_RVA_OFF, 0);
+
+		*decoder = new FLVMP3(ctx);
+		return CREATEDECODER_SUCCESS;
+	}
+	return CREATEDECODER_NOT_MINE;
+}
+
+int FLVDecoderCreator::HandlesAudio(int format_type)
+{
+	if (format_type == FLV::AUDIO_FORMAT_MP3 || format_type == FLV::AUDIO_FORMAT_MP3_8KHZ)
+	{
+		return CREATEDECODER_SUCCESS;
+	}
+	return CREATEDECODER_NOT_MINE;
+}
+
+#define CBCLASS FLVDecoderCreator
+START_DISPATCH;
+CB(CREATE_AUDIO_DECODER, CreateAudioDecoder)
+CB(HANDLES_AUDIO, HandlesAudio)
+END_DISPATCH;
+#undef CBCLASS
+
+/* --- */
+#define FHG_DELAY 529
+FLVMP3::FLVMP3(mpg123_handle *mp3) : mp3(mp3)
+{
+	mpg123_open_feed(mp3);
+	bits = 16;
+	pregap = FHG_DELAY;
+	max_channels = 2;
+	channels = 0;
+	decode_buffer = 0;
+	decode_buffer_length = 0;
+}
+
+FLVMP3::~FLVMP3()
+{
+	if (mp3) {
+		mpg123_delete(mp3);
+		mp3 = 0;
+	}
+	free(decode_buffer);
+}
+
+int FLVMP3::GetOutputFormat(unsigned int *sample_rate, unsigned int *_channels, unsigned int *_bits)
+{
+	mpg123_frameinfo frameInfo;
+	if (mpg123_info(mp3, &frameInfo) == MPG123_OK)
+	{
+		*sample_rate = frameInfo.rate;
+		channels = (frameInfo.mode == MPG123_M_MONO)?1:2;
+		*_channels = channels;
+		*_bits = bits;
+		return FLV_AUDIO_SUCCESS;
+	}
+	else
+	{
+		return FLV_AUDIO_FAILURE;
+	}
+}
+
+int FLVMP3::DecodeSample(const void *input_buffer, size_t input_buffer_bytes, void *samples, size_t *samples_size_bytes, double *bitrate)
+{
+	if (!mp3)
+		return FLV_AUDIO_FAILURE;
+
+	mpg123_feed(mp3, (unsigned char *)input_buffer, input_buffer_bytes);
+
+	*samples_size_bytes = 0;
+	*bitrate = 0;
+
+	for (;;) {
+		if (!decode_buffer) {
+			int channels = 2;
+			long sample_rate;
+			int encoding;
+			if (mpg123_getformat(mp3, &sample_rate, &channels, &encoding) == MPG123_OK) {
+				this->channels = channels;
+				decode_buffer_length = sizeof(float) * channels * mpg123_spf(mp3);
+				decode_buffer = (float *)malloc(decode_buffer_length);
+				if (!decode_buffer) {
+					return FLV_AUDIO_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 (!channels) {
+				long sample_rate = 44100;
+				int channels = 2;
+				int encoding = 0;
+				if (mpg123_getformat(mp3, &sample_rate, &channels, &encoding) == MPG123_OK) {
+					this->channels = channels;
+				} else {
+					return FLV_AUDIO_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(samples, pcm_buf, bits, numSamples);
+
+			*samples_size_bytes += numSamples * bits / 8;
+			samples = (char *)samples + numSamples * bits / 8;
+
+			mpg123_frameinfo frameInfo;
+			if (mpg123_info(mp3, &frameInfo) == MPG123_OK) {
+				*bitrate = frameInfo.bitrate;
+			}
+			return FLV_AUDIO_SUCCESS;
+		} else if (err == MPG123_NEED_MORE) {
+			*samples_size_bytes = 0;
+			return FLV_AUDIO_NEEDS_MORE_INPUT;
+		} else if (err == MPG123_NEW_FORMAT) {
+			continue;
+		} else if (err == MPG123_OK) {
+			continue;
+		}
+		else
+			return FLV_AUDIO_FAILURE;
+	}
+	return FLV_AUDIO_SUCCESS;
+}
+
+void FLVMP3::Flush()
+{
+	mpg123_open_feed(mp3);
+	pregap = FHG_DELAY;
+}
+
+void FLVMP3::Close()
+{
+	if (mp3) {
+		mpg123_delete(mp3);
+		mp3 = 0;
+	}
+	delete this;
+}
+
+void FLVMP3::SetPreferences(unsigned int _max_channels, unsigned int preferred_bits)
+{
+	if (preferred_bits)
+		bits = preferred_bits;
+
+	if (max_channels > _max_channels)
+		max_channels = _max_channels;
+
+	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(mp3, MPG123_FLAGS, flags, 0);
+	mpg123_param(mp3, MPG123_RVA, MPG123_RVA_OFF, 0);
+
+}
+
+#define CBCLASS FLVMP3
+START_DISPATCH;
+CB(FLV_AUDIO_GETOUTPUTFORMAT, GetOutputFormat)
+CB(FLV_AUDIO_DECODE, DecodeSample)
+VCB(FLV_AUDIO_FLUSH, Flush)
+VCB(FLV_AUDIO_CLOSE, Close)
+VCB(FLV_AUDIO_SETPREFERENCES, SetPreferences)
+END_DISPATCH;
+#undef CBCLASS