diff --git a/src/layout/interleave.c b/src/layout/interleave.c
index 1e99ee4f..d5d5319e 100644
--- a/src/layout/interleave.c
+++ b/src/layout/interleave.c
@@ -1,33 +1,12 @@
 #include "interleave.h"
-#include "../coding/adx_decoder.h"
-#include "../coding/gcdsp_decoder.h"
-#include "../coding/pcm_decoder.h"
+#include "../vgmstream.h"
 
 void render_vgmstream_interleave(sample * buffer, int32_t sample_count, VGMSTREAM * vgmstream) {
     int samples_written=0;
 
-    int frame_size;
-    int samples_per_frame;
+    int frame_size = get_vgmstream_frame_size(vgmstream);
+    int samples_per_frame = get_vgmstream_samples_per_frame(vgmstream);;
     int samples_this_block;
-    switch (vgmstream->coding_type) {
-        case coding_CRI_ADX:
-            frame_size=18;
-            samples_per_frame=32;
-            break;
-        case coding_NGC_DSP:
-            frame_size=8;
-            samples_per_frame=14;
-            break;
-        case coding_PCM16LE:
-        case coding_PCM16BE:
-            frame_size=2;
-            samples_per_frame=1;
-            break;
-        case coding_PCM8:
-            frame_size=1;
-            samples_per_frame=1;
-            break;
-    }
 
     samples_this_block = vgmstream->interleave_block_size / frame_size * samples_per_frame;
 
@@ -106,44 +85,7 @@ void render_vgmstream_interleave(sample * buffer, int32_t sample_count, VGMSTREA
         if (samples_written+samples_to_do > sample_count)
             samples_to_do=sample_count-samples_written;
 
-        switch (vgmstream->coding_type) {
-            case coding_CRI_ADX:
-                for (chan=0;chan<vgmstream->channels;chan++) {
-                    decode_adx(&vgmstream->ch[chan],buffer+samples_written*vgmstream->channels+chan,
-                            vgmstream->channels,vgmstream->samples_into_block,
-                            samples_to_do);
-                }
-
-                break;
-            case coding_NGC_DSP:
-                for (chan=0;chan<vgmstream->channels;chan++) {
-                    decode_gcdsp(&vgmstream->ch[chan],buffer+samples_written*vgmstream->channels+chan,
-                            vgmstream->channels,vgmstream->samples_into_block,
-                            samples_to_do);
-                }
-                break;
-            case coding_PCM16LE:
-                for (chan=0;chan<vgmstream->channels;chan++) {
-                    decode_pcm16LE(&vgmstream->ch[chan],buffer+samples_written*vgmstream->channels+chan,
-                            vgmstream->channels,vgmstream->samples_into_block,
-                            samples_to_do);
-                }
-                break;
-            case coding_PCM16BE:
-                for (chan=0;chan<vgmstream->channels;chan++) {
-                    decode_pcm16BE(&vgmstream->ch[chan],buffer+samples_written*vgmstream->channels+chan,
-                            vgmstream->channels,vgmstream->samples_into_block,
-                            samples_to_do);
-                }
-                break;
-            case coding_PCM8:
-                for (chan=0;chan<vgmstream->channels;chan++) {
-                    decode_pcm8(&vgmstream->ch[chan],buffer+samples_written*vgmstream->channels+chan,
-                            vgmstream->channels,vgmstream->samples_into_block,
-                            samples_to_do);
-                }
-                break;
-        }
+        decode_vgmstream(vgmstream, samples_written, samples_to_do, buffer);
 
         samples_written += samples_to_do;
         vgmstream->current_sample += samples_to_do;
diff --git a/src/layout/nolayout.c b/src/layout/nolayout.c
index e99983a5..d52d6a1a 100644
--- a/src/layout/nolayout.c
+++ b/src/layout/nolayout.c
@@ -1,27 +1,11 @@
 #include "nolayout.h"
-#include "../coding/adx_decoder.h"
-#include "../coding/gcdsp_decoder.h"
-#include "../coding/pcm_decoder.h"
+#include "../vgmstream.h"
 
 void render_vgmstream_nolayout(sample * buffer, int32_t sample_count, VGMSTREAM * vgmstream) {
     int samples_written=0;
 
     const int samples_this_block = vgmstream->num_samples;
-    int samples_per_frame;
-
-    switch(vgmstream->coding_type) {
-        case coding_CRI_ADX:
-            samples_per_frame = 32;
-            break;
-        case coding_NGC_DSP:
-            samples_per_frame = 14;
-            break;
-        case coding_PCM16LE:
-        case coding_PCM16BE:
-        case coding_PCM8:
-            samples_per_frame = 1;
-            break;
-    }
+    int samples_per_frame = get_vgmstream_samples_per_frame(vgmstream);
 
     while (samples_written<sample_count) {
         int samples_to_do;
@@ -74,23 +58,7 @@ void render_vgmstream_nolayout(sample * buffer, int32_t sample_count, VGMSTREAM
         if (samples_written+samples_to_do > sample_count)
             samples_to_do=sample_count-samples_written;
 
-        switch (vgmstream->coding_type) {
-            case coding_CRI_ADX:
-                for (chan=0;chan<vgmstream->channels;chan++) {
-                    decode_adx(&vgmstream->ch[chan],buffer+samples_written*vgmstream->channels+chan,
-                            vgmstream->channels,vgmstream->samples_into_block,
-                            samples_to_do);
-                }
-
-                break;
-            case coding_NGC_DSP:
-                for (chan=0;chan<vgmstream->channels;chan++) {
-                    decode_gcdsp(&vgmstream->ch[chan],buffer+samples_written*vgmstream->channels+chan,
-                            vgmstream->channels,vgmstream->samples_into_block,
-                            samples_to_do);
-                }
-                break;
-        }
+        decode_vgmstream(vgmstream, samples_written, samples_to_do, buffer);
 
         samples_written += samples_to_do;
         vgmstream->current_sample += samples_to_do;
diff --git a/src/vgmstream.c b/src/vgmstream.c
index 74c0a23d..a62fd9fc 100644
--- a/src/vgmstream.c
+++ b/src/vgmstream.c
@@ -3,6 +3,9 @@
 #include "meta/brstm.h"
 #include "layout/interleave.h"
 #include "layout/nolayout.h"
+#include "coding/adx_decoder.h"
+#include "coding/gcdsp_decoder.h"
+#include "coding/pcm_decoder.h"
 
 /*
  * List of functions that will recognize files. These should correspond pretty
@@ -111,3 +114,77 @@ void render_vgmstream(sample * buffer, int32_t sample_count, VGMSTREAM * vgmstre
             break;
     }
 }
+
+int get_vgmstream_samples_per_frame(VGMSTREAM * vgmstream) {
+    switch (vgmstream->coding_type) {
+        case coding_CRI_ADX:
+            return 32;
+        case coding_NGC_DSP:
+            return 14;
+        case coding_PCM16LE:
+        case coding_PCM16BE:
+        case coding_PCM8:
+            return 1;
+        default:
+            return 0;
+    }
+}
+
+int get_vgmstream_frame_size(VGMSTREAM * vgmstream) {
+    switch (vgmstream->coding_type) {
+        case coding_CRI_ADX:
+            return 18;
+        case coding_NGC_DSP:
+            return 8;
+        case coding_PCM16LE:
+        case coding_PCM16BE:
+            return 2;
+        case coding_PCM8:
+            return 1;
+        default:
+            return 0;
+    }
+}
+
+void decode_vgmstream(VGMSTREAM * vgmstream, int samples_written, int samples_to_do, sample * buffer) {
+    int chan;
+
+    switch (vgmstream->coding_type) {
+        case coding_CRI_ADX:
+            for (chan=0;chan<vgmstream->channels;chan++) {
+                decode_adx(&vgmstream->ch[chan],buffer+samples_written*vgmstream->channels+chan,
+                        vgmstream->channels,vgmstream->samples_into_block,
+                        samples_to_do);
+            }
+
+            break;
+        case coding_NGC_DSP:
+            for (chan=0;chan<vgmstream->channels;chan++) {
+                decode_gcdsp(&vgmstream->ch[chan],buffer+samples_written*vgmstream->channels+chan,
+                        vgmstream->channels,vgmstream->samples_into_block,
+                        samples_to_do);
+            }
+            break;
+        case coding_PCM16LE:
+            for (chan=0;chan<vgmstream->channels;chan++) {
+                decode_pcm16LE(&vgmstream->ch[chan],buffer+samples_written*vgmstream->channels+chan,
+                        vgmstream->channels,vgmstream->samples_into_block,
+                        samples_to_do);
+            }
+            break;
+        case coding_PCM16BE:
+            for (chan=0;chan<vgmstream->channels;chan++) {
+                decode_pcm16BE(&vgmstream->ch[chan],buffer+samples_written*vgmstream->channels+chan,
+                        vgmstream->channels,vgmstream->samples_into_block,
+                        samples_to_do);
+            }
+            break;
+        case coding_PCM8:
+            for (chan=0;chan<vgmstream->channels;chan++) {
+                decode_pcm8(&vgmstream->ch[chan],buffer+samples_written*vgmstream->channels+chan,
+                        vgmstream->channels,vgmstream->samples_into_block,
+                        samples_to_do);
+            }
+            break;
+    }
+}
diff --git a/src/vgmstream.h b/src/vgmstream.h
index a3f1d860..80e619bd 100644
--- a/src/vgmstream.h
+++ b/src/vgmstream.h
@@ -144,4 +144,9 @@ int32_t get_vgmstream_play_samples(double looptimes, double fadetime, VGMSTREAM
 /* render! */
 void render_vgmstream(sample * buffer, int32_t sample_count, VGMSTREAM * vgmstream);
 
+int get_vgmstream_samples_per_frame(VGMSTREAM * vgmstream);
+int get_vgmstream_frame_size(VGMSTREAM * vgmstream);
+
+void decode_vgmstream(VGMSTREAM * vgmstream, int samples_written, int samples_to_do, sample * buffer);
+
 #endif