From 0bf6e36628291855701de14e8575ac6fa5e25341 Mon Sep 17 00:00:00 2001
From: Jens Arnold <amiconn@rockbox.org>
Date: Sun, 21 Dec 2008 01:29:36 +0000
Subject: [PATCH] Fix handling of 8 bit mono and stereo APE files, and also
 optimise 16 and 24 bit output in the standalone decoder a bit.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@19517 a1c6a512-1295-4272-9138-f99709370657
---
 apps/codecs/demac/demac.c            | 26 ++++++++++-----
 apps/codecs/demac/libdemac/decoder.c | 47 ++++++++++++----------------
 2 files changed, 38 insertions(+), 35 deletions(-)

diff --git a/apps/codecs/demac/demac.c b/apps/codecs/demac/demac.c
index da132ff248..5e9893687d 100644
--- a/apps/codecs/demac/demac.c
+++ b/apps/codecs/demac/demac.c
@@ -2,7 +2,7 @@
 
 demac - A Monkey's Audio decoder
 
-$Id:$
+$Id$
 
 Copyright (C) Dave Chapman 2007
 
@@ -180,17 +180,27 @@ int ape_decode(char* infile, char* outfile)
 
             /* Convert the output samples to WAV format and write to output file */
             p = wavbuffer;
-            if (ape_ctx.bps == 16) {
+            if (ape_ctx.bps == 8) {
+                for (i = 0 ; i < blockstodecode ; i++)
+                {
+                    /* 8 bit WAV uses unsigned samples */
+                    *(p++) = (decoded0[i] + 0x80) & 0xff;
+
+                    if (ape_ctx.channels == 2) {
+                        *(p++) = (decoded1[i] + 0x80) & 0xff;
+                    }
+                }
+            } else if (ape_ctx.bps == 16) {
                 for (i = 0 ; i < blockstodecode ; i++)
                 {
                     sample16 = decoded0[i];
                     *(p++) = sample16 & 0xff;
-                    *(p++) = (sample16&0xff00) >> 8;
+                    *(p++) = (sample16 >> 8) & 0xff;
 
                     if (ape_ctx.channels == 2) {
                         sample16 = decoded1[i];
                         *(p++) = sample16 & 0xff;
-                        *(p++) = (sample16&0xff00) >> 8;
+                        *(p++) = (sample16 >> 8) & 0xff;
                     }
                 }
             } else if (ape_ctx.bps == 24) {
@@ -198,14 +208,14 @@ int ape_decode(char* infile, char* outfile)
                 {
                     sample32 = decoded0[i];
                     *(p++) = sample32 & 0xff;
-                    *(p++) = (sample32&0xff00) >> 8;
-                    *(p++) = (sample32&0xff0000) >> 16;
+                    *(p++) = (sample32 >> 8) & 0xff;
+                    *(p++) = (sample32 >> 16) & 0xff;
 
                     if (ape_ctx.channels == 2) {
                         sample32 = decoded1[i];
                         *(p++) = sample32 & 0xff;
-                        *(p++) = (sample32&0xff00) >> 8;
-                        *(p++) = (sample32&0xff0000) >> 16;
+                        *(p++) = (sample32 >> 8) & 0xff;
+                        *(p++) = (sample32 >> 16) & 0xff;
                     }
                 }
             }
diff --git a/apps/codecs/demac/libdemac/decoder.c b/apps/codecs/demac/libdemac/decoder.c
index 79b5255ce0..2200faf187 100644
--- a/apps/codecs/demac/libdemac/decoder.c
+++ b/apps/codecs/demac/libdemac/decoder.c
@@ -91,14 +91,14 @@ int ICODE_ATTR_DEMAC decode_chunk(struct ape_ctx_t* ape_ctx,
 #endif
 
     if ((ape_ctx->channels==1) || (ape_ctx->frameflags & APE_FRAMECODE_PSEUDO_STEREO)) {
-        if (ape_ctx->frameflags & APE_FRAMECODE_STEREO_SILENCE) {
+        if (ape_ctx->frameflags & APE_FRAMECODE_STEREO_SILENCE) { 
             entropy_decode(ape_ctx, inbuffer, firstbyte, bytesconsumed, decoded0, decoded1, count);
             /* We are pure silence, so we're done. */
             return 0;
         } else {
             entropy_decode(ape_ctx, inbuffer, firstbyte, bytesconsumed, decoded0, NULL, count);
         }
-    
+
         switch (ape_ctx->compressiontype)
         {
             case 2000:
@@ -124,26 +124,23 @@ int ICODE_ATTR_DEMAC decode_chunk(struct ape_ctx_t* ape_ctx,
         predictor_decode_mono(&ape_ctx->predictor,decoded0,count);
 
         if (ape_ctx->channels==2) {
-            /* Pseudo-stereo - just copy left channel to right channel */
+            /* Pseudo-stereo - copy left channel to right channel */
             while (count--)
             {
                 left = *decoded0;
                 *(decoded1++) = *(decoded0++) = SCALE(left);
             }
-        } else {
-            /* Mono - do nothing unless it's 8-bit audio */
-            if (ape_ctx->bps == 8) {
-                /* TODO: Handle 8-bit streams */
-            } else {
-                /* Scale to output depth */
-                while (count--)
-                {
-                    left = *decoded0;
-                    *(decoded0++) = SCALE(left);
-                }    
-            }
-
         }
+#ifdef ROCKBOX
+         else {
+            /* Scale to output depth */
+            while (count--)
+            {
+                left = *decoded0;
+                *(decoded0++) = SCALE(left);
+            }
+        }
+#endif
     } else { /* Stereo */
         if (ape_ctx->frameflags & APE_FRAMECODE_STEREO_SILENCE) {
             /* We are pure silence, so we're done. */
@@ -177,18 +174,14 @@ int ICODE_ATTR_DEMAC decode_chunk(struct ape_ctx_t* ape_ctx,
         /* Now apply the predictor decoding */
         predictor_decode_stereo(&ape_ctx->predictor,decoded0,decoded1,count);
 
-        if (ape_ctx->bps == 8) {
-            /* TODO: Handle 8-bit streams */
-        } else {
-            /* Decorrelate and scale to output depth */
-            while (count--)
-            {
-                left = *decoded1 - (*decoded0 / 2);
-                right = left + *decoded0;
+        /* Decorrelate and scale to output depth */
+        while (count--)
+        {
+            left = *decoded1 - (*decoded0 / 2);
+            right = left + *decoded0;
 
-                *(decoded0++) = SCALE(left);
-                *(decoded1++) = SCALE(right);
-            }
+            *(decoded0++) = SCALE(left);
+            *(decoded1++) = SCALE(right);
         }
     }
     return 0;