[WIP] seamless playback

1 files changed, 89 insertions, 67 deletions

diff --git a/streamer.c b/streamer.c
index 1c72775f..7023c5a7 100644
--- a/streamer.c
+++ b/streamer.c
@@ -10,9 +10,9 @@ 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!
+static char g_readbuffer[200000]; // hack!
+static float g_fbuffer[200000]; // hack!
+static float g_srcbuffer[200000]; // hack!
 
 int
 streamer_init (void) {
@@ -33,80 +33,102 @@ streamer_free (void) {
     }
 }
 
+void
+streamer_reset (void) { // must be called when current song changes by external reasons
+    codecleft = 0;
+    src_reset (src);
+}
+
 // 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);
+    int initsize = size;
+    for (;;) {
+        int bytesread = 0;
+        codec_lock ();
+        codec_t *codec = playlist_current.codec;
+        if (!codec) {
             codec_unlock ();
+            break;
         }
-        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;
+        int nchannels = codec->info.channels;
+        int samplerate = codec->info.samplesPerSecond;
+        // read and do SRC
+        if (codec->info.samplesPerSecond == sdl_player_freq) {
+            int i;
+            if (codec->info.channels == 2) {
+                bytesread = codec->read (bytes, size);
+                codec_unlock ();
             }
-            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 {
+                bytesread = codec->read (g_readbuffer, size/2);
+                codec_unlock ();
+                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;
             }
         }
-        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];
+        else {
+            int nsamples = size/4;
+            // convert to codec samplerate
+            nsamples = nsamples * samplerate / sdl_player_freq * 2 ;
+            // read data at source samplerate (with some room for SRC)
+            int nbytes = (nsamples - codecleft) * 2 * nchannels;
+            bytesread = codec->read (g_readbuffer, nbytes);
+            codec_unlock ();
+            // recalculate nsamples according to how many bytes we've got
+            nsamples = bytesread / (2 * nchannels) + codecleft;
+            // convert to float
+            int i;
+            float *fbuffer = g_fbuffer + codecleft*2;
+            if (nchannels == 2) {
+                for (i = 0; i < (nsamples - codecleft) * 2; i++) {
+                    fbuffer[i] = ((int16_t *)g_readbuffer)[i]/32767.f;
+                }
+            }
+            else if (nchannels == 1) { // convert mono to stereo
+                for (i = 0; i < (nsamples - codecleft); i++) {
+                    fbuffer[i*2+0] = ((int16_t *)g_readbuffer)[i]/32767.f;
+                    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/samplerate;
+            srcdata.end_of_input = 0;
+//            src_set_ratio (src, srcdata.src_ratio);
+            src_process (src, &srcdata);
+            //printf ("processed %d/%d samples (input=%d)\n", srcdata.output_frames_gen, srcdata.output_frames, srcdata.input_frames);
+            // 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 (g_fbuffer, &g_fbuffer[srcdata.input_frames_used*2], codecleft * 8);
         }
-        // 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);
+        bytes += bytesread;
+        size -= bytesread;
+        if (size == 0) {
+            return initsize;
+        }
+        else {
+            //printf ("eof (size=%d)\n", size);
+            // that means EOF
+            if (ps_nextsong () < 0) {
+                break;
+            }
         }
-        // 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;
+    return initsize - size;
 }