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diff --git a/gp2x/mp3.c b/gp2x/mp3.c
new file mode 100644
index 0000000..e37b774
--- /dev/null
+++ b/gp2x/mp3.c
@@ -0,0 +1,134 @@
+#include <stdio.h>
+#include <string.h>
+
+#include "../../Pico/sound/mix.h"
+#include "code940/940shared.h"
+#include "helix/pub/mp3dec.h"
+
+static short mp3_out_buffer[2*1152];
+static HMP3Decoder mp3dec = 0;
+static int mp3_buffer_offs = 0;
+
+extern _940_ctl_t *shared_ctl;
+extern unsigned char *mp3_mem;
+extern int PsndRate;
+
+
+static int try_get_header(unsigned char *buff, MP3FrameInfo *fi)
+{
+	int ret, offs1, offs = 0;
+
+	while (1)
+	{
+		offs1 = MP3FindSyncWord(buff + offs, 2048 - offs);
+		if (offs1 < 0) return -2;
+		offs += offs1;
+		if (2048 - offs < 4) return -3;
+
+		// printf("trying header %08x\n", *(int *)(buff + offs));
+
+		ret = MP3GetNextFrameInfo(mp3dec, fi, buff + offs);
+		if (ret == 0 && fi->bitrate != 0) break;
+		offs++;
+	}
+
+	return ret;
+}
+
+int mp3_get_bitrate(FILE *f, int len)
+{
+	unsigned char buff[2048];
+	MP3FrameInfo fi;
+	int ret;
+
+	memset(buff, 0, 2048);
+
+	if (!mp3dec) mp3dec = MP3InitDecoder();
+
+	fseek(f, 0, SEEK_SET);
+	ret = fread(buff, 1, 2048, f);
+	fseek(f, 0, SEEK_SET);
+	if (ret <= 0) return -1;
+
+	ret = try_get_header(buff, &fi);
+	if (ret != 0 || fi.bitrate == 0) {
+		// try to read somewhere around the middle
+		fseek(f, len>>1, SEEK_SET);
+		fread(buff, 1, 2048, f);
+		fseek(f, 0, SEEK_SET);
+		ret = try_get_header(buff, &fi);
+	}
+	if (ret != 0) return ret;
+
+	// printf("bitrate: %i\n", fi.bitrate / 1000);
+
+	return fi.bitrate / 1000;
+}
+
+
+static void mp3_decode(void)
+{
+	// tried copying this to cached mem, no improvement noticed
+	int mp3_offs = shared_ctl->mp3_offs;
+	unsigned char *readPtr = mp3_mem + mp3_offs;
+	int bytesLeft = shared_ctl->mp3_len - mp3_offs;
+	int offset; // frame offset from readPtr
+	int err;
+
+	if (bytesLeft <= 0) return; // EOF, nothing to do
+
+	offset = MP3FindSyncWord(readPtr, bytesLeft);
+	if (offset < 0) {
+		shared_ctl->mp3_offs = shared_ctl->mp3_len;
+		return; // EOF
+	}
+	readPtr += offset;
+	bytesLeft -= offset;
+
+	err = MP3Decode(mp3dec, &readPtr, &bytesLeft, mp3_out_buffer, 0);
+	if (err) {
+		if (err == ERR_MP3_INDATA_UNDERFLOW) {
+			shared_ctl->mp3_offs = shared_ctl->mp3_len; // EOF
+			return;
+		} else if (err <= -6 && err >= -12) {
+			// ERR_MP3_INVALID_FRAMEHEADER, ERR_MP3_INVALID_*
+			// just try to skip the offending frame..
+			readPtr++;
+		}
+		shared_ctl->mp3_errors++;
+		shared_ctl->mp3_lasterr = err;
+	}
+	shared_ctl->mp3_offs = readPtr - mp3_mem;
+}
+
+
+void mp3_update_local(int *buffer, int length, int stereo)
+{
+	int length_mp3, shr = 0;
+	void (*mix_samples)(int *dest_buf, short *mp3_buf, int count) = mix_16h_to_32;
+
+	length_mp3 = length;
+	if (PsndRate == 22050) { mix_samples = mix_16h_to_32_s1; length_mp3 <<= 1; shr = 1; }
+	else if (PsndRate == 11025) { mix_samples = mix_16h_to_32_s2; length_mp3 <<= 2; shr = 2; }
+
+	if (1152 - mp3_buffer_offs >= length_mp3) {
+		mix_samples(buffer, mp3_out_buffer + mp3_buffer_offs*2, length<<1);
+
+		mp3_buffer_offs += length_mp3;
+	} else {
+		int left = 1152 - mp3_buffer_offs;
+
+		mix_samples(buffer, mp3_out_buffer + mp3_buffer_offs*2, (left>>shr)<<1);
+		mp3_decode();
+		mp3_buffer_offs = length_mp3 - left;
+		mix_samples(buffer + ((left>>shr)<<1), mp3_out_buffer, (mp3_buffer_offs>>shr)<<1);
+	}
+}
+
+
+void mp3_start_local(void)
+{
+	mp3_buffer_offs = 0;
+	mp3_decode();
+}
+