Add MP3 Support

Signed-off-by: Mahyar Koshkouei <deltabeard@users.noreply.github.com>
2017-01-05 21:12:03 +00:00
parent 2456166647
commit 28d2e8d594
7 changed files with 191 additions and 3 deletions
--- a/source/mp3.c
+++ b/source/mp3.c
@@ -0,0 +1,159 @@
+#include <3ds.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "all.h"
+#include "mp3.h"
+
+int playMp3(const char* in)
+{
+	int				err = 0;
+	mpg123_handle	*mh = NULL;
+	size_t			buffer_size = 0;
+	size_t			done = 0;
+	long			rate = 0;
+	int				channels = 0;
+	int				encoding = 0;
+	unsigned char*	buffer1 = NULL;
+	unsigned char*	buffer2 = NULL;
+	int				ret = 0;
+	ndspWaveBuf		waveBuf[2];
+	bool			playing = true;
+	bool			lastbuf = false;
+
+	if(R_FAILED(ndspInit()))
+	{
+		printf("Initialising ndsp failed.");
+		goto out;
+	}
+
+	if((err = mpg123_init()) != MPG123_OK)
+		return err;
+
+	if((mh = mpg123_new(NULL, &err)) == NULL)
+	{
+		printf("Error: %s\n", mpg123_plain_strerror(err));
+		goto err;
+	}
+
+	if(mpg123_open(mh, in) != MPG123_OK ||
+			mpg123_getformat(mh, &rate, &channels, &encoding) != MPG123_OK)
+	{
+		printf("Trouble with mpg123: %s\n", mpg123_strerror(mh));
+		goto err;
+	}
+
+	/* Ensure that this output format will not change
+	   (it might, when we allow it). */
+	mpg123_format_none(mh);
+	mpg123_format(mh, rate, channels, encoding);
+
+	/* Buffer could be almost any size here, mpg123_outblock() is just some
+	   recommendation. The size should be a multiple of the PCM frame size. */
+	buffer_size = mpg123_outblock(mh) * 16;
+	buffer1 = linearAlloc(buffer_size);
+	buffer2 = linearAlloc(buffer_size);
+
+	/* I'm not sure if this error will ever occur. */
+	if(channels > 2)
+	{
+		printf("Invalid number of channels %d\n", channels);
+		goto err;
+	}
+
+	ndspChnReset(CHANNEL);
+	ndspChnWaveBufClear(CHANNEL);
+	ndspSetOutputMode(NDSP_OUTPUT_STEREO);
+	ndspChnSetInterp(CHANNEL, NDSP_INTERP_POLYPHASE);
+	ndspChnSetRate(CHANNEL, rate);
+	ndspChnSetFormat(CHANNEL,
+			channels == 2 ? NDSP_FORMAT_STEREO_PCM16 : NDSP_FORMAT_MONO_PCM16);
+
+	memset(waveBuf, 0, sizeof(waveBuf));
+
+	mpg123_read(mh, buffer1, buffer_size, &done);
+	waveBuf[0].nsamples = done / (sizeof(s16) * channels);
+	waveBuf[0].data_vaddr = &buffer1[0];
+	ndspChnWaveBufAdd(CHANNEL, &waveBuf[0]);
+
+	mpg123_read(mh, buffer2, buffer_size, &done);
+	waveBuf[1].nsamples = done / (sizeof(s16) * channels);
+	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;
+
+		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)
+		{
+			err = mpg123_read(mh, buffer1, buffer_size, &done);
+
+			if(err != MPG123_OK)
+			{
+				lastbuf = true;
+				continue;
+			}
+
+			ndspChnWaveBufAdd(CHANNEL, &waveBuf[0]);
+		}
+
+		if(waveBuf[1].status == NDSP_WBUF_DONE)
+		{
+			err = mpg123_read(mh, buffer2, buffer_size, &done);
+
+			if(err != MPG123_OK)
+			{
+				lastbuf = true;
+				continue;
+			}
+
+			ndspChnWaveBufAdd(CHANNEL, &waveBuf[1]);
+		}
+
+		DSP_FlushDataCache(buffer1, buffer_size);
+		DSP_FlushDataCache(buffer2, buffer_size);
+	}
+
+out:
+	linearFree(buffer1);
+	linearFree(buffer2);
+	ndspChnWaveBufClear(CHANNEL);
+	ndspExit();
+	mpg123_close(mh);
+	mpg123_delete(mh);
+	mpg123_exit();
+	printf("\nStopping MP3 playback.\n");
+	return ret;
+
+err:
+	ret = -1;
+	goto out;
+}