[WIP] disabled most codecs, moved streaming out of psdl

1 files changed, 112 insertions, 0 deletions

diff --git a/streamer.c b/streamer.c
new file mode 100644
index 00000000..1c72775f
--- /dev/null
+++ b/streamer.c
@@ -0,0 +1,112 @@
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <samplerate.h>
+#include "codec.h"
+#include "playlist.h"
+#include "common.h"
+
+extern int sdl_player_freq; // hack!
+static SRC_STATE *src;
+static SRC_DATA srcdata;
+static int codecleft;
+static char g_readbuffer[20000]; // hack!
+static float g_fbuffer[20000]; // hack!
+static float g_srcbuffer[20000]; // hack!
+
+int
+streamer_init (void) {
+//    src = src_new (SRC_LINEAR, 2, NULL);
+    src = src_new (SRC_SINC_BEST_QUALITY, 2, NULL);
+    if (!src) {
+        return -1;
+    }
+    codecleft = 0;
+    return 0;
+}
+
+void
+streamer_free (void) {
+    if (src) {
+        src_delete (src);
+        src = NULL;
+    }
+}
+
+// returns number of bytes been read
+int
+streamer_read (char *bytes, int size) {
+    codec_t *codec = playlist_current.codec;
+    int bytesread = 0;
+    if (!codec) {
+        return 0;
+    }
+    // read and do SRC
+    if (codec->info.samplesPerSecond == sdl_player_freq) {
+        int i;
+        if (codec->info.channels == 2) {
+            codec_lock ();
+            bytesread = codec->read (bytes, size);
+            codec_unlock ();
+        }
+        else {
+            codec_lock ();
+            bytesread = codec->read (g_readbuffer, size/2);
+            for (i = 0; i < size/4; i++) {
+                int16_t sample = (int16_t)(((int32_t)(((int16_t*)g_readbuffer)[i])));
+                ((int16_t*)bytes)[i*2+0] = sample;
+                ((int16_t*)bytes)[i*2+1] = sample;
+            }
+            bytesread *= 2;
+            codec_unlock ();
+        }
+    }
+    else {
+        int nsamples = size/4;
+        // convert to codec samplerate
+        // add 5 extra samples for SRC
+        nsamples = nsamples * codec->info.samplesPerSecond / sdl_player_freq + 5;
+        // read data at source samplerate (with some room for SRC)
+        codec_lock ();
+        int nbytes = (nsamples - codecleft) * 2 * codec->info.channels;
+        bytesread = codec->read (g_readbuffer, nbytes);
+        // recalculate nsamples according to how many bytes we've got
+        nsamples -= (nbytes - bytesread) / (2 * codec->info.channels);
+        // convert to float, and apply soft volume
+        int i;
+        float *fbuffer = g_fbuffer + codecleft*2;
+        if (codec->info.channels == 2) { // convert mono to stereo
+            for (i = 0; i < (nsamples - codecleft) * 2; i++) {
+                fbuffer[i] = ((int16_t *)g_readbuffer)[i]/32767.f;
+            }
+        }
+        else if (codec->info.channels == 1) {
+            for (i = 0; i < (nsamples - codecleft); i++) {
+                fbuffer[i*2+0] = ((int16_t *)g_readbuffer)[i];
+                fbuffer[i*2+1] = fbuffer[i*2+0];
+            }
+        }
+        // convert samplerate
+        srcdata.data_in = g_fbuffer;
+        srcdata.data_out = g_srcbuffer;
+        srcdata.input_frames = nsamples;
+        srcdata.output_frames = size/4;
+        srcdata.src_ratio = (double)sdl_player_freq/codec->info.samplesPerSecond;
+        srcdata.end_of_input = 0;
+        src_process (src, &srcdata);
+        // convert back to s16 format
+        nbytes = size;
+        int genbytes = srcdata.output_frames_gen * 4;
+        bytesread = min(size, genbytes);
+
+        for (i = 0; i < bytesread/2; i++) {
+            ((int16_t*)bytes)[i] = (int16_t)(g_srcbuffer[i]*32767.f);
+        }
+        // calculate how many unused input samples left
+        codecleft = nsamples - srcdata.input_frames_used;
+        // copy spare samples for next update
+        memmove (fbuffer, &fbuffer[srcdata.input_frames_used*2], codecleft * 8);
+        codec_unlock ();
+    }
+    return bytesread;
+}