Refactor Opus decoder

Created generic playback handler, first with Opus support. Other
decoders to follow. This is to remove duplicated code.

3DSX tested working with citra and N3DS.

Signed-off-by: Mahyar Koshkouei <deltabeard@users.noreply.github.com>

source/all.h

@@ -4,9 +4,19 @@
 #define CHANNEL	0x08
 
 /* Adds extra debugging text */
-//#define DEBUG
+#define DEBUG
 
 /* Prints more error information */
 #define err_print(err) \
 	do { fprintf(stderr, "\nError %d:%s(): %s %s\n", __LINE__, __func__, \
 			err, strerror(errno)); } while (0)
+
+struct decoder_fn
+{
+	int (* init)(const char* file);
+	uint32_t (* rate)(void);
+	uint8_t channels;
+	int buffSize;
+	uint64_t (* decode)(void*);
+	void (* exit)(void);
+};

source/main.c

@@ -20,22 +20,9 @@
 #include "main.h"
 #include "mp3.h"
 #include "opus.h"
+#include "playback.h"
 #include "wav.h"
 
-/* Default folder */
-#define DEFAULT_DIR		"sdmc:/"
-/* Maximum number of lines that can be displayed */
-#define	MAX_LIST		27
-
-enum file_types {
-	FILE_TYPE_ERROR = -1,
-	FILE_TYPE_WAV,
-	FILE_TYPE_FLAC,
-	FILE_TYPE_OGG,
-	FILE_TYPE_OPUS,
-	FILE_TYPE_MP3
-};
-
 int main(int argc, char **argv)
 {
 	PrintConsole	topScreen;
@@ -204,6 +191,7 @@ int main(int argc, char **argv)
 				else
 				{
 					consoleSelect(&topScreen);
+					/* Move this to playback.c */
 					switch(getFileType(file))
 					{
 						case FILE_TYPE_WAV:
@@ -215,7 +203,7 @@ int main(int argc, char **argv)
 							break;
 
 						case FILE_TYPE_OPUS:
-							playOpus(file);
+							playFile(file);
 							break;
 
 						case FILE_TYPE_MP3:

source/main.h

@@ -7,6 +7,21 @@
  * LICENSE file.
  */
 
+/* Default folder */
+#define DEFAULT_DIR		"sdmc:/"
+
+/* Maximum number of lines that can be displayed */
+#define	MAX_LIST		27
+
+enum file_types {
+	FILE_TYPE_ERROR = -1,
+	FILE_TYPE_WAV,
+	FILE_TYPE_FLAC,
+	FILE_TYPE_OGG,
+	FILE_TYPE_OPUS,
+	FILE_TYPE_MP3
+};
+
 /**
  * Get number of files in current working folder
  *

source/opus.c

@@ -7,146 +7,84 @@
 
 #define SAMPLES_TO_READ	(32 * 1024)
 
-int playOpus(const char* in)
+static OggOpusFile*		opusFile;
+static const OpusHead*	opusHead;
+
+/**
+ * Set decoder parameters for Opus.
+ *
+ * \param	decoder	Structure to store parameters.
+ */
+void setOpus(struct decoder_fn* decoder)
 {
-	int				err = 0;
+	decoder->init = initOpus;
-	int16_t*		buffer1 = linearAlloc(SAMPLES_TO_READ * sizeof(int16_t));
+	decoder->rate = rateOpus;
-	int16_t*		buffer2 = linearAlloc(SAMPLES_TO_READ * sizeof(int16_t));
+	/* Opus decoder always returns stereo stream */
-	ndspWaveBuf 	waveBuf[2];
+	decoder->channels = 2;
-	bool			playing = true;
+	decoder->buffSize = SAMPLES_TO_READ;
-	bool			lastbuf = false;
+	decoder->decode = decodeOpus;
-	OggOpusFile*	opusFile = op_open_file(in, &err);
+	decoder->exit = exitOpus;
-	const OpusHead*	opusHead;
-	int				link;
-
-	if(err != 0)
-	{
-		printf("libopusfile failed with error %d.", err);
-		return -1;
-	}
-
-	if(R_FAILED(ndspInit()))
-	{
-		printf("Initialising ndsp failed.");
-		goto out;
-	}
-
-	if((link = op_current_link(opusFile)) < 0)
-	{
-		printf("Error getting current link: %d\n", link);
-		goto out;
-	}
-
-	opusHead = op_head(opusFile, link);
-#ifdef DEBUG
-	printf("\nRate: %lu\tChan: %d\n", opusHead->input_sample_rate,
-			opusHead->channel_count);
-#endif
-
-	ndspChnReset(CHANNEL);
-	ndspChnWaveBufClear(CHANNEL);
-	ndspSetOutputMode(NDSP_OUTPUT_STEREO);
-	ndspChnSetInterp(CHANNEL, NDSP_INTERP_POLYPHASE);
-	ndspChnSetRate(CHANNEL, opusHead->input_sample_rate);
-	ndspChnSetFormat(CHANNEL, NDSP_FORMAT_STEREO_PCM16);
-
-	memset(waveBuf, 0, sizeof(waveBuf));
-	waveBuf[0].nsamples =
-		fillOpusBuffer(opusFile, SAMPLES_TO_READ, buffer1) / 2;
-	waveBuf[0].data_vaddr = &buffer1[0];
-	ndspChnWaveBufAdd(CHANNEL, &waveBuf[0]);
-
-	waveBuf[1].nsamples =
-		fillOpusBuffer(opusFile, SAMPLES_TO_READ, buffer2) / 2;
-	waveBuf[1].data_vaddr = &buffer2[0];
-	ndspChnWaveBufAdd(CHANNEL, &waveBuf[1]);
-
-	printf("Playing %s\n", in);
-	/**
-	 * There may be a chance that the music has not started by the time we get
-	 * to the while loop. So we ensure that music has started here.
-	 */
-	while(ndspChnIsPlaying(CHANNEL) == false);
-
-	while(playing == false || ndspChnIsPlaying(CHANNEL) == true)
-	{
-		u32 kDown;
-
-		/* Number of bytes read from file.
-		 * Static only for the purposes of the printf debug at the bottom.
-		 */
-		static size_t read = 0;
-
-		gfxSwapBuffers();
-		gfxFlushBuffers();
-		gspWaitForVBlank();
-
-		hidScanInput();
-		kDown = hidKeysDown();
-
-		if(kDown & KEY_B)
-			break;
-
-		if(kDown & (KEY_A | KEY_R))
-		{
-			playing = !playing;
-			printf("\33[2K\r%s", playing == false ? "Paused" : "");
-		}
-
-		if(playing == false || lastbuf == true)
-			continue;
-
-		if(waveBuf[0].status == NDSP_WBUF_DONE)
-		{
-			read = fillOpusBuffer(opusFile, SAMPLES_TO_READ, buffer1);
-
-			if(read == 0)
-			{
-				lastbuf = true;
-				continue;
-			}
-			else if(read < SAMPLES_TO_READ)
-				waveBuf[0].nsamples = read / opusHead->channel_count;
-
-			ndspChnWaveBufAdd(CHANNEL, &waveBuf[0]);
-		}
-
-		if(waveBuf[1].status == NDSP_WBUF_DONE)
-		{
-			read = fillOpusBuffer(opusFile, SAMPLES_TO_READ, buffer2);
-
-			if(read == 0)
-			{
-				lastbuf = true;
-				continue;
-			}
-			else if(read < SAMPLES_TO_READ)
-				waveBuf[1].nsamples = read / opusHead->channel_count;
-
-			ndspChnWaveBufAdd(CHANNEL, &waveBuf[1]);
-		}
-
-		DSP_FlushDataCache(buffer1, SAMPLES_TO_READ * sizeof(s16));
-		DSP_FlushDataCache(buffer2, SAMPLES_TO_READ * sizeof(s16));
-	}
-
-out:
-	printf("\nStopping Opus playback.\n");
-	ndspChnWaveBufClear(CHANNEL);
-	ndspExit();
-	linearFree(buffer1);
-	linearFree(buffer2);
-	op_free(opusFile);
-	return 0;
 }
 
 /**
- * Fill a buffer with decoded samples.
+ * Initialise Opus decoder.
  *
- * \param opusFile		OggOpusFile pointer.
+ * \param	file	Location of opus file to play.
- * \param samplesToRead	Number of samples to read in to buffer.
+ * \return			0 on success, else failure.
- * \param bufferOut		Pointer to output buffer.
+ */
- * \return				Number of samples read per channel.
+int initOpus(const char* file)
+{
+	int err = 0;
+
+	if((opusFile = op_open_file(file, &err)) == NULL)
+		goto out;
+
+	if((err = op_current_link(opusFile)) < 0)
+		goto out;
+
+	opusHead = op_head(opusFile, err);
+
+out:
+	return err;
+}
+
+/**
+ * Get sampling rate of Opus file.
+ *
+ * \return	Sampling rate. Should be 48000.
+ */
+uint32_t rateOpus(void)
+{
+	return opusHead->input_sample_rate;
+}
+
+/**
+ * Decode part of open Opus file.
+ *
+ * \param buffer	Decoded output.
+ * \return			Samples read for each channel.
+ */
+uint64_t decodeOpus(void* buffer)
+{
+	return fillOpusBuffer(opusFile, SAMPLES_TO_READ, buffer);
+}
+
+/**
+ * Free Opus decoder.
+ */
+void exitOpus(void)
+{
+	op_free(opusFile);
+}
+
+/**
+ * Decode Opus file to fill buffer.
+ *
+ * \param opusFile		File to decode.
+ * \param samplesToRead	Number of samples to read in to buffer. Must not exceed
+ *						size of buffer.
+ * \param bufferOut		Pointer to buffer.
+ * \return				Samples read per channel.
  */
 uint64_t fillOpusBuffer(OggOpusFile* opusFile, uint64_t samplesToRead,
 		int16_t* bufferOut)

source/opus.h

@@ -1,5 +1,15 @@
 #include <opus/opusfile.h>
 
+void setOpus(struct decoder_fn* decoder);
+
+int initOpus(const char* file);
+
+uint32_t rateOpus(void);
+
+uint64_t decodeOpus(void* buffer);
+
+void exitOpus(void);
+
 int playOpus(const char* in);
 
 uint64_t fillOpusBuffer(OggOpusFile* opusFile, uint64_t samplesToRead,

source/playback.c

@@ -0,0 +1,138 @@
+#include <3ds.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "all.h"
+#include "opus.h"
+#include "playback.h"
+
+int playFile(const char* file)
+{
+	struct decoder_fn decoder;
+	int16_t*		buffer1 = NULL;
+	int16_t*		buffer2 = NULL;
+	ndspWaveBuf		waveBuf[2];
+	bool			playing = true;
+	bool			lastbuf = false;
+
+	printf("Here: %d\n", __LINE__);
+	if(R_FAILED(ndspInit()))
+	{
+		printf("Initialising ndsp failed.");
+		goto out;
+	}
+
+	printf("Here: %d\n", __LINE__);
+	setOpus(&decoder);
+
+	printf("Here: %d\n", __LINE__);
+	buffer1 = linearAlloc(decoder.buffSize * sizeof(int16_t));
+	buffer2 = linearAlloc(decoder.buffSize * sizeof(int16_t));
+
+	printf("Here: %d\n", __LINE__);
+	if((*decoder.init)(file) != 0)
+		goto out;
+
+	printf("Here: %d\n", __LINE__);
+
+#ifdef DEBUG
+	printf("\nRate: %lu\tChan: %d\n", (*decoder.rate)(), decoder.channels);
+#endif
+
+	ndspChnReset(CHANNEL);
+	ndspChnWaveBufClear(CHANNEL);
+	ndspSetOutputMode(NDSP_OUTPUT_STEREO);
+	ndspChnSetInterp(CHANNEL, NDSP_INTERP_POLYPHASE);
+	ndspChnSetRate(CHANNEL, (*decoder.rate)());
+	ndspChnSetFormat(CHANNEL, NDSP_FORMAT_STEREO_PCM16);
+	printf("Here: %d\n", __LINE__);
+
+	memset(waveBuf, 0, sizeof(waveBuf));
+	waveBuf[0].nsamples = (*decoder.decode)(&buffer1[0]) / decoder.channels;
+	waveBuf[0].data_vaddr = &buffer1[0];
+	ndspChnWaveBufAdd(CHANNEL, &waveBuf[0]);
+	printf("Here: %d\n", __LINE__);
+
+	waveBuf[1].nsamples = (*decoder.decode)(&buffer2[0]) / decoder.channels;
+	waveBuf[1].data_vaddr = &buffer2[0];
+	ndspChnWaveBufAdd(CHANNEL, &waveBuf[1]);
+
+	printf("Playing %s\n", file);
+
+	/**
+	 * There may be a chance that the music has not started by the time we get
+	 * to the while loop. So we ensure that music has started here.
+	 */
+	while(ndspChnIsPlaying(CHANNEL) == false);
+
+	while(playing == false || ndspChnIsPlaying(CHANNEL) == true)
+	{
+		u32 kDown;
+
+		/* Number of bytes read from file.
+		 * Static only for the purposes of the printf debug at the bottom.
+		 */
+		static size_t read = 0;
+
+		gfxSwapBuffers();
+		gfxFlushBuffers();
+		gspWaitForVBlank();
+
+		hidScanInput();
+		kDown = hidKeysDown();
+
+		if(kDown & KEY_B)
+			break;
+
+		if(kDown & (KEY_A | KEY_R))
+		{
+			playing = !playing;
+			printf("\33[2K\r%s", playing == false ? "Paused" : "");
+		}
+
+		if(playing == false || lastbuf == true)
+			continue;
+
+		if(waveBuf[0].status == NDSP_WBUF_DONE)
+		{
+			read = (*decoder.decode)(&buffer1[0]);
+
+			if(read == 0)
+			{
+				lastbuf = true;
+				continue;
+			}
+			else if(read < decoder.buffSize)
+				waveBuf[0].nsamples = read / decoder.channels;
+
+			ndspChnWaveBufAdd(CHANNEL, &waveBuf[0]);
+		}
+
+		if(waveBuf[1].status == NDSP_WBUF_DONE)
+		{
+			read = (*decoder.decode)(&buffer2[0]);
+
+			if(read == 0)
+			{
+				lastbuf = true;
+				continue;
+			}
+			else if(read < decoder.buffSize)
+				waveBuf[1].nsamples = read / decoder.channels;
+
+			ndspChnWaveBufAdd(CHANNEL, &waveBuf[1]);
+		}
+
+		DSP_FlushDataCache(buffer1, decoder.buffSize * sizeof(int16_t));
+		DSP_FlushDataCache(buffer2, decoder.buffSize * sizeof(int16_t));
+	}
+
+out:
+	printf("\nStopping playback.\n");
+	(*decoder.exit)();
+	ndspChnWaveBufClear(CHANNEL);
+	ndspExit();
+	linearFree(buffer1);
+	linearFree(buffer2);
+	return 0;
+}

source/playback.h

@@ -0,0 +1 @@
+int playFile(const char* file);