From 23f602a07a570de8a3a356b6b156fe036c38ab27 Mon Sep 17 00:00:00 2001
From: "H. Peter Anvin" <hpa@zytor.com>
Date: Tue, 5 Sep 2006 17:06:14 -0700
Subject: [PATCH] Augment tinyjpeg so that we can decode straight into the
 buffer; clear the screen on startup.

---
 com32/include/tinyjpeg.h           |  6 ++++--
 com32/lib/jpeg/bgr24.c             | 17 ++++++++++-------
 com32/lib/jpeg/bgra32.c            | 21 +++++++++++---------
 com32/lib/jpeg/grey.c              | 23 +++++++++++++++-------
 com32/lib/jpeg/rgb24.c             | 17 ++++++++++-------
 com32/lib/jpeg/rgba32.c            | 17 ++++++++++-------
 com32/lib/jpeg/tinyjpeg-internal.h |  1 +
 com32/lib/jpeg/tinyjpeg.c          | 38 ++++++++++++++++++++++++++++---------
 com32/lib/jpeg/yuv420p.c           | 39 ++++++++++++++++++++++----------------
 com32/lib/sys/vesa/background.c    | 30 ++++++++++++-----------------
 com32/lib/sys/vesa/initvesa.c      |  2 +-
 11 files changed, 128 insertions(+), 83 deletions(-)

diff --git a/com32/include/tinyjpeg.h b/com32/include/tinyjpeg.h
index b800a4b..d320f9b 100644
--- a/com32/include/tinyjpeg.h
+++ b/com32/include/tinyjpeg.h
@@ -59,8 +59,10 @@ int tinyjpeg_parse_header(struct jdec_private *priv, const unsigned char *buf, u
 int tinyjpeg_decode(struct jdec_private *priv, tinyjpeg_colorspace_t pixel_format);
 const char *tinyjpeg_get_errorstring(struct jdec_private *priv);
 void tinyjpeg_get_size(struct jdec_private *priv, unsigned int *width, unsigned int *height);
-int tinyjpeg_get_components(struct jdec_private *priv, unsigned char **components);
-int tinyjpeg_set_components(struct jdec_private *priv, unsigned char **components, unsigned int ncomponents);
+int tinyjpeg_get_components(struct jdec_private *priv, unsigned char **components, unsigned int ncomponents);
+int tinyjpeg_set_components(struct jdec_private *priv, unsigned char * const *components, unsigned int ncomponents);
+int tinyjpeg_get_bytes_per_row(struct jdec_private *priv, unsigned int *bytes, unsigned int ncomponents);
+int tinyjpeg_set_bytes_per_row(struct jdec_private *priv, const unsigned int *bytes, unsigned int ncomponents);
 int tinyjpeg_set_flags(struct jdec_private *priv, int flags);
 
 #ifdef __cplusplus
diff --git a/com32/lib/jpeg/bgr24.c b/com32/lib/jpeg/bgr24.c
index 465d58e..3f2f4f9 100644
--- a/com32/lib/jpeg/bgr24.c
+++ b/com32/lib/jpeg/bgr24.c
@@ -84,7 +84,7 @@ static void YCrCB_to_BGR24_1x1(struct jdec_private *priv)
   Y = priv->Y;
   Cb = priv->Cb;
   Cr = priv->Cr;
-  offset_to_next_row = priv->width*3 - 8*3;
+  offset_to_next_row = priv->bytes_per_row[0] - 8*3;
   for (i=0; i<8; i++) {
 
     for (j=0;j<8;j++) {
@@ -140,7 +140,7 @@ static void YCrCB_to_BGR24_2x1(struct jdec_private *priv)
   Y = priv->Y;
   Cb = priv->Cb;
   Cr = priv->Cr;
-  offset_to_next_row = priv->width*3 - 16*3;
+  offset_to_next_row = priv->bytes_per_row[0] - 16*3;
   for (i=0; i<8; i++) {
 
     for (j=0; j<8; j++) {
@@ -202,11 +202,11 @@ static void YCrCB_to_BGR24_1x2(struct jdec_private *priv)
 #define FIX(x)          ((int)((x) * (1UL<<SCALEBITS) + 0.5))
 
   p = priv->plane[0];
-  p2 = priv->plane[0] + priv->width*3;
+  p2 = priv->plane[0] + priv->bytes_per_row[0];
   Y = priv->Y;
   Cb = priv->Cb;
   Cr = priv->Cr;
-  offset_to_next_row = 2*priv->width*3 - 8*3;
+  offset_to_next_row = 2*priv->bytes_per_row[0] - 8*3;
   for (i=0; i<8; i++) {
 
     for (j=0; j<8; j++) {
@@ -270,11 +270,11 @@ static void YCrCB_to_BGR24_2x2(struct jdec_private *priv)
 #define FIX(x)          ((int)((x) * (1UL<<SCALEBITS) + 0.5))
 
   p = priv->plane[0];
-  p2 = priv->plane[0] + priv->width*3;
+  p2 = priv->plane[0] + priv->bytes_per_row[0];
   Y = priv->Y;
   Cb = priv->Cb;
   Cr = priv->Cr;
-  offset_to_next_row = (priv->width*3*2) - 16*3;
+  offset_to_next_row = 2*priv->bytes_per_row[0] - 16*3;
   for (i=0; i<8; i++) {
 
     for (j=0;j<8;j++) {
@@ -338,7 +338,10 @@ static int initialize_bgr24(struct jdec_private *priv,
 {
   if (priv->components[0] == NULL)
     priv->components[0] = (uint8_t *)malloc(priv->width * priv->height * 3);
-  bytes_per_blocklines[0] = priv->width * 3;
+  if (!priv->bytes_per_row[0])
+    priv->bytes_per_row[0] = priv->width * 3;
+
+  bytes_per_blocklines[0] = priv->bytes_per_row[0];
   bytes_per_mcu[0] = 3*8;
 
   return !priv->components[0];
diff --git a/com32/lib/jpeg/bgra32.c b/com32/lib/jpeg/bgra32.c
index ba0db70..fe6b813 100644
--- a/com32/lib/jpeg/bgra32.c
+++ b/com32/lib/jpeg/bgra32.c
@@ -84,7 +84,7 @@ static void YCrCB_to_BGRA32_1x1(struct jdec_private *priv)
   Y = priv->Y;
   Cb = priv->Cb;
   Cr = priv->Cr;
-  offset_to_next_row = priv->width*4 - 8*4;
+  offset_to_next_row = priv->bytes_per_row[0] - 8*4;
   for (i=0; i<8; i++) {
 
     for (j=0;j<8;j++) {
@@ -142,7 +142,7 @@ static void YCrCB_to_BGRA32_2x1(struct jdec_private *priv)
   Y = priv->Y;
   Cb = priv->Cb;
   Cr = priv->Cr;
-  offset_to_next_row = priv->width*4 - 16*4;
+  offset_to_next_row = priv->bytes_per_row[0] - 16*4;
   for (i=0; i<8; i++) {
 
     for (j=0; j<8; j++) {
@@ -208,11 +208,11 @@ static void YCrCB_to_BGRA32_1x2(struct jdec_private *priv)
 #define FIX(x)          ((int)((x) * (1UL<<SCALEBITS) + 0.5))
 
   p = priv->plane[0];
-  p2 = priv->plane[0] + priv->width*4;
+  p2 = priv->plane[0] + priv->bytes_per_row[0];
   Y = priv->Y;
   Cb = priv->Cb;
   Cr = priv->Cr;
-  offset_to_next_row = 2*priv->width*4 - 8*4;
+  offset_to_next_row = 2*priv->bytes_per_row[0] - 8*4;
   for (i=0; i<8; i++) {
 
     for (j=0; j<8; j++) {
@@ -280,11 +280,11 @@ static void YCrCB_to_BGRA32_2x2(struct jdec_private *priv)
 #define FIX(x)          ((int)((x) * (1UL<<SCALEBITS) + 0.5))
 
   p = priv->plane[0];
-  p2 = priv->plane[0] + priv->width*4;
+  p2 = priv->plane[0] + priv->bytes_per_row[0];
   Y = priv->Y;
   Cb = priv->Cb;
   Cr = priv->Cr;
-  offset_to_next_row = (priv->width*4*2) - 16*4;
+  offset_to_next_row = 2*priv->bytes_per_row[0] - 16*4;
   for (i=0; i<8; i++) {
 
     for (j=0;j<8;j++) {
@@ -351,12 +351,15 @@ static void YCrCB_to_BGRA32_2x2(struct jdec_private *priv)
 }
 
 static int initialize_bgra32(struct jdec_private *priv,
-			    unsigned int *bytes_per_blocklines,
-			    unsigned int *bytes_per_mcu)
+			     unsigned int *bytes_per_blocklines,
+			     unsigned int *bytes_per_mcu)
 {
   if (priv->components[0] == NULL)
     priv->components[0] = (uint8_t *)malloc(priv->width * priv->height * 4);
-  bytes_per_blocklines[0] = priv->width * 4;
+  if (!priv->bytes_per_row[0])
+    priv->bytes_per_row[0] = priv->width * 4;
+
+  bytes_per_blocklines[0] = priv->bytes_per_row[0];
   bytes_per_mcu[0] = 4*8;
 
   return !priv->components[0];
diff --git a/com32/lib/jpeg/grey.c b/com32/lib/jpeg/grey.c
index edeb74a..bb55b7e 100644
--- a/com32/lib/jpeg/grey.c
+++ b/com32/lib/jpeg/grey.c
@@ -54,7 +54,7 @@ static void YCrCB_to_Grey_1x1(struct jdec_private *priv)
 
   p = priv->plane[0];
   y = priv->Y;
-  offset_to_next_row = priv->width;
+  offset_to_next_row = priv->bytes_per_row[0];
 
   for (i=0; i<8; i++) {
      memcpy(p, y, 8);
@@ -74,14 +74,16 @@ static void YCrCB_to_Grey_2x1(struct jdec_private *priv)
   const unsigned char *y;
   unsigned char *p;
   unsigned int i;
+  int offset_to_next_row;
 
   p = priv->plane[0];
   y = priv->Y;
+  offset_to_next_row = priv->bytes_per_row[0];
 
   for (i=0; i<8; i++) {
      memcpy(p, y, 16);
      y += 16;
-     p += priv->width;
+     p += offset_to_next_row;
   }
 }
 
@@ -99,14 +101,16 @@ static void YCrCB_to_Grey_1x2(struct jdec_private *priv)
   const unsigned char *y;
   unsigned char *p;
   unsigned int i;
+  int offset_to_next_row;
 
   p = priv->plane[0];
   y = priv->Y;
+  offset_to_next_row = priv->bytes_per_row[0];
 
   for (i=0; i<16; i++) {
      memcpy(p, y, 8);
      y += 8;
-     p += priv->width;
+     p += offset_to_next_row;
   }
 }
 
@@ -123,24 +127,29 @@ static void YCrCB_to_Grey_2x2(struct jdec_private *priv)
   const unsigned char *y;
   unsigned char *p;
   unsigned int i;
+  int offset_to_next_row;
 
   p = priv->plane[0];
   y = priv->Y;
+  offset_to_next_row = priv->bytes_per_row[0];
 
   for (i=0; i<16; i++) {
      memcpy(p, y, 16);
      y += 16;
-     p += priv->width;
+     p += offset_to_next_row;
   }
 }
 
 static int initialize_grey(struct jdec_private *priv,
-			    unsigned int *bytes_per_blocklines,
-			    unsigned int *bytes_per_mcu)
+			   unsigned int *bytes_per_blocklines,
+			   unsigned int *bytes_per_mcu)
 {
   if (priv->components[0] == NULL)
     priv->components[0] = (uint8_t *)malloc(priv->width * priv->height * 3);
-  bytes_per_blocklines[0] = priv->width * 3;
+  if (!priv->bytes_per_row[0])
+    priv->bytes_per_row[0] = priv->width * 3;
+
+  bytes_per_blocklines[0] = priv->bytes_per_row[0];
   bytes_per_mcu[0] = 3*8;
 
   return !priv->components[0];
diff --git a/com32/lib/jpeg/rgb24.c b/com32/lib/jpeg/rgb24.c
index 65c0695..d3ee07a 100644
--- a/com32/lib/jpeg/rgb24.c
+++ b/com32/lib/jpeg/rgb24.c
@@ -84,7 +84,7 @@ static void YCrCB_to_RGB24_1x1(struct jdec_private *priv)
   Y = priv->Y;
   Cb = priv->Cb;
   Cr = priv->Cr;
-  offset_to_next_row = priv->width*3 - 8*3;
+  offset_to_next_row = priv->bytes_per_row[0] - 8*3;
   for (i=0; i<8; i++) {
 
     for (j=0;j<8;j++) {
@@ -139,7 +139,7 @@ static void YCrCB_to_RGB24_2x1(struct jdec_private *priv)
   Y = priv->Y;
   Cb = priv->Cb;
   Cr = priv->Cr;
-  offset_to_next_row = priv->width*3 - 16*3;
+  offset_to_next_row = priv->bytes_per_row[0] - 16*3;
   for (i=0; i<8; i++) {
 
     for (j=0; j<8; j++) {
@@ -202,11 +202,11 @@ static void YCrCB_to_RGB24_1x2(struct jdec_private *priv)
 #define FIX(x)          ((int)((x) * (1UL<<SCALEBITS) + 0.5))
 
   p = priv->plane[0];
-  p2 = priv->plane[0] + priv->width*3;
+  p2 = priv->plane[0] + priv->bytes_per_row[0];
   Y = priv->Y;
   Cb = priv->Cb;
   Cr = priv->Cr;
-  offset_to_next_row = 2*priv->width*3 - 8*3;
+  offset_to_next_row = 2*priv->bytes_per_row[0] - 8*3;
   for (i=0; i<8; i++) {
 
     for (j=0; j<8; j++) {
@@ -269,11 +269,11 @@ static void YCrCB_to_RGB24_2x2(struct jdec_private *priv)
 #define FIX(x)          ((int)((x) * (1UL<<SCALEBITS) + 0.5))
 
   p = priv->plane[0];
-  p2 = priv->plane[0] + priv->width*3;
+  p2 = priv->plane[0] + priv->bytes_per_row[0];
   Y = priv->Y;
   Cb = priv->Cb;
   Cr = priv->Cr;
-  offset_to_next_row = (priv->width*3*2) - 16*3;
+  offset_to_next_row = 2*priv->bytes_per_row[0] - 16*3;
   for (i=0; i<8; i++) {
 
     for (j=0;j<8;j++) {
@@ -337,7 +337,10 @@ static int initialize_rgb24(struct jdec_private *priv,
 {
   if (priv->components[0] == NULL)
     priv->components[0] = (uint8_t *)malloc(priv->width * priv->height * 3);
-  bytes_per_blocklines[0] = priv->width * 3;
+  if (!priv->bytes_per_row[0])
+    priv->bytes_per_row[0] = priv->width * 3;
+
+  bytes_per_blocklines[0] = priv->bytes_per_row[0];
   bytes_per_mcu[0] = 3*8;
 
   return !priv->components[0];
diff --git a/com32/lib/jpeg/rgba32.c b/com32/lib/jpeg/rgba32.c
index 2934bcd..2ad9112 100644
--- a/com32/lib/jpeg/rgba32.c
+++ b/com32/lib/jpeg/rgba32.c
@@ -84,7 +84,7 @@ static void YCrCB_to_RGBA32_1x1(struct jdec_private *priv)
   Y = priv->Y;
   Cb = priv->Cb;
   Cr = priv->Cr;
-  offset_to_next_row = priv->width*4 - 8*4;
+  offset_to_next_row = priv->bytes_per_row[0] - 8*4;
   for (i=0; i<8; i++) {
 
     for (j=0;j<8;j++) {
@@ -140,7 +140,7 @@ static void YCrCB_to_RGBA32_2x1(struct jdec_private *priv)
   Y = priv->Y;
   Cb = priv->Cb;
   Cr = priv->Cr;
-  offset_to_next_row = priv->width*4 - 16*4;
+  offset_to_next_row = priv->bytes_per_row[0] - 16*4;
   for (i=0; i<8; i++) {
 
     for (j=0; j<8; j++) {
@@ -206,11 +206,11 @@ static void YCrCB_to_RGBA32_1x2(struct jdec_private *priv)
 #define FIX(x)          ((int)((x) * (1UL<<SCALEBITS) + 0.5))
 
   p = priv->plane[0];
-  p2 = priv->plane[0] + priv->width*4;
+  p2 = priv->plane[0] + priv->bytes_per_row[0];
   Y = priv->Y;
   Cb = priv->Cb;
   Cr = priv->Cr;
-  offset_to_next_row = 2*priv->width*4 - 8*4;
+  offset_to_next_row = 2*priv->bytes_per_row[0] - 8*4;
   for (i=0; i<8; i++) {
 
     for (j=0; j<8; j++) {
@@ -277,11 +277,11 @@ static void YCrCB_to_RGBA32_2x2(struct jdec_private *priv)
 #define FIX(x)          ((int)((x) * (1UL<<SCALEBITS) + 0.5))
 
   p = priv->plane[0];
-  p2 = priv->plane[0] + priv->width*4;
+  p2 = priv->plane[0] + priv->bytes_per_row[0];
   Y = priv->Y;
   Cb = priv->Cb;
   Cr = priv->Cr;
-  offset_to_next_row = (priv->width*4*2) - 16*4;
+  offset_to_next_row = 2*priv->bytes_per_row[0] - 16*4;
   for (i=0; i<8; i++) {
 
     for (j=0;j<8;j++) {
@@ -353,7 +353,10 @@ static int initialize_rgba32(struct jdec_private *priv,
 {
   if (priv->components[0] == NULL)
     priv->components[0] = (uint8_t *)malloc(priv->width * priv->height * 4);
-  bytes_per_blocklines[0] = priv->width * 4;
+  if (!priv->bytes_per_row[0])
+    priv->bytes_per_row[0] = priv->width * 4;
+
+  bytes_per_blocklines[0] = priv->bytes_per_row[0];
   bytes_per_mcu[0] = 4*8;
 
   return !priv->components[0];
diff --git a/com32/lib/jpeg/tinyjpeg-internal.h b/com32/lib/jpeg/tinyjpeg-internal.h
index abad084..a414581 100644
--- a/com32/lib/jpeg/tinyjpeg-internal.h
+++ b/com32/lib/jpeg/tinyjpeg-internal.h
@@ -76,6 +76,7 @@ struct jdec_private
 {
   /* Public variables */
   uint8_t *components[COMPONENTS];
+  unsigned int bytes_per_row[COMPONENTS];
   unsigned int width, height;	/* Size of the image */
   unsigned int flags;
 
diff --git a/com32/lib/jpeg/tinyjpeg.c b/com32/lib/jpeg/tinyjpeg.c
index ca180a0..a93a512 100644
--- a/com32/lib/jpeg/tinyjpeg.c
+++ b/com32/lib/jpeg/tinyjpeg.c
@@ -787,12 +787,6 @@ int tinyjpeg_decode(struct jdec_private *priv,
   const decode_MCU_fct *decode_mcu_table;
   convert_colorspace_fct convert_to_pixfmt;
 
-  /* To keep gcc happy initialize some array */
-  bytes_per_mcu[1] = 0;
-  bytes_per_mcu[2] = 0;
-  bytes_per_blocklines[1] = 0;
-  bytes_per_blocklines[2] = 0;
-
   decode_mcu_table = pixfmt->decode_mcu_table;
 
   /* Fix: check return value */
@@ -864,15 +858,17 @@ void tinyjpeg_get_size(struct jdec_private *priv, unsigned int *width, unsigned
   *height = priv->height;
 }
 
-int tinyjpeg_get_components(struct jdec_private *priv, unsigned char **components)
+int tinyjpeg_get_components(struct jdec_private *priv, unsigned char **components, unsigned int ncomponents)
 {
   int i;
-  for (i=0; priv->components[i] && i<COMPONENTS; i++)
+  if (ncomponents > COMPONENTS)
+    ncomponents = COMPONENTS;
+  for (i=0; i<ncomponents; i++)
     components[i] = priv->components[i];
   return 0;
 }
 
-int tinyjpeg_set_components(struct jdec_private *priv, unsigned char **components, unsigned int ncomponents)
+int tinyjpeg_set_components(struct jdec_private *priv, unsigned char * const *components, unsigned int ncomponents)
 {
   int i;
   if (ncomponents > COMPONENTS)
@@ -882,6 +878,30 @@ int tinyjpeg_set_components(struct jdec_private *priv, unsigned char **component
   return 0;
 }
 
+int tinyjpeg_get_bytes_per_row(struct jdec_private *priv,
+			       unsigned int *bytes,
+			       unsigned int ncomponents)
+{
+  int i;
+  if (ncomponents > COMPONENTS)
+    ncomponents = COMPONENTS;
+  for (i=0; i<ncomponents; i++)
+    bytes[i] = priv->bytes_per_row[i];
+  return 0;
+}  
+
+int tinyjpeg_set_bytes_per_row(struct jdec_private *priv,
+			       const unsigned int *bytes,
+			       unsigned int ncomponents)
+{
+  int i;
+  if (ncomponents > COMPONENTS)
+    ncomponents = COMPONENTS;
+  for (i=0; i<ncomponents; i++)
+    priv->bytes_per_row[i] = bytes[i];
+  return 0;
+}  
+
 int tinyjpeg_set_flags(struct jdec_private *priv, int flags)
 {
   int oldflags = priv->flags;
diff --git a/com32/lib/jpeg/yuv420p.c b/com32/lib/jpeg/yuv420p.c
index 5411aa8..6d2bd05 100644
--- a/com32/lib/jpeg/yuv420p.c
+++ b/com32/lib/jpeg/yuv420p.c
@@ -60,8 +60,8 @@ static void YCrCB_to_YUV420P_1x1(struct jdec_private *priv)
   for (i=0; i<8; i++)
    {
      memcpy(p, y, 8);
-     p+=priv->width;
-     y+=8;
+     p += priv->bytes_per_row[0];
+     y += 8;
    }
 
   p = priv->plane[1];
@@ -71,7 +71,7 @@ static void YCrCB_to_YUV420P_1x1(struct jdec_private *priv)
      for (j=0; j<8; j+=2, s+=2)
        *p++ = *s;
      s += 8; /* Skip one line */
-     p += priv->width/2 - 4;
+     p += priv->bytes_per_row[1] - 4;
    }
 
   p = priv->plane[2];
@@ -81,7 +81,7 @@ static void YCrCB_to_YUV420P_1x1(struct jdec_private *priv)
      for (j=0; j<8; j+=2, s+=2)
        *p++ = *s;
      s += 8; /* Skip one line */
-     p += priv->width/2 - 4;
+     p += priv->bytes_per_row[2] - 4;
    }
 }
 
@@ -102,7 +102,7 @@ static void YCrCB_to_YUV420P_2x1(struct jdec_private *priv)
   for (i=0; i<8; i++)
    {
      memcpy(p, y1, 16);
-     p += priv->width;
+     p += priv->bytes_per_row[0];
      y1 += 16;
    }
 
@@ -113,7 +113,7 @@ static void YCrCB_to_YUV420P_2x1(struct jdec_private *priv)
      for (j=0; j<8; j+=1, s+=1)
        *p++ = *s;
      s += 8; /* Skip one line */
-     p += priv->width/2 - 8;
+     p += priv->bytes_per_row[1] - 8;
    }
 
   p = priv->plane[2];
@@ -123,7 +123,7 @@ static void YCrCB_to_YUV420P_2x1(struct jdec_private *priv)
      for (j=0; j<8; j+=1, s+=1)
        *p++ = *s;
      s += 8; /* Skip one line */
-     p += priv->width/2 - 8;
+     p += priv->bytes_per_row[2] - 8;
    }
 }
 
@@ -147,7 +147,7 @@ static void YCrCB_to_YUV420P_1x2(struct jdec_private *priv)
   for (i=0; i<16; i++)
    {
      memcpy(p, y, 8);
-     p+=priv->width;
+     p+=priv->bytes_per_row[0];
      y+=8;
    }
 
@@ -157,7 +157,7 @@ static void YCrCB_to_YUV420P_1x2(struct jdec_private *priv)
    {
      for (j=0; j<8; j+=2, s+=2)
        *p++ = *s;
-     p += priv->width/2 - 4;
+     p += priv->bytes_per_row[1] - 4;
    }
 
   p = priv->plane[2];
@@ -166,7 +166,7 @@ static void YCrCB_to_YUV420P_1x2(struct jdec_private *priv)
    {
      for (j=0; j<8; j+=2, s+=2)
        *p++ = *s;
-     p += priv->width/2 - 4;
+     p += priv->bytes_per_row[2] - 4;
    }
 }
 
@@ -189,7 +189,7 @@ static void YCrCB_to_YUV420P_2x2(struct jdec_private *priv)
   for (i=0; i<16; i++)
    {
      memcpy(p, y1, 16);
-     p += priv->width;
+     p += priv->bytes_per_row[0];
      y1 += 16;
    }
 
@@ -199,7 +199,7 @@ static void YCrCB_to_YUV420P_2x2(struct jdec_private *priv)
    {
      memcpy(p, s, 8);
      s += 8;
-     p += priv->width/2;
+     p += priv->bytes_per_row[1];
    }
 
   p = priv->plane[2];
@@ -208,7 +208,7 @@ static void YCrCB_to_YUV420P_2x2(struct jdec_private *priv)
    {
      memcpy(p, s, 8);
      s += 8;
-     p += priv->width/2;
+     p += priv->bytes_per_row[2];
    }
 }
 
@@ -222,9 +222,16 @@ static int initialize_yuv420p(struct jdec_private *priv,
     priv->components[1] = (uint8_t *)malloc(priv->width * priv->height/4);
   if (priv->components[2] == NULL)
     priv->components[2] = (uint8_t *)malloc(priv->width * priv->height/4);
-  bytes_per_blocklines[0] = priv->width;
-  bytes_per_blocklines[1] = priv->width/4;
-  bytes_per_blocklines[2] = priv->width/4;
+  if (!priv->bytes_per_row[0])
+    priv->bytes_per_row[0] = priv->width;
+  if (!priv->bytes_per_row[1])
+    priv->bytes_per_row[1] = priv->width/2;
+  if (!priv->bytes_per_row[2])
+    priv->bytes_per_row[2] = priv->width/2;
+
+  bytes_per_blocklines[0] = priv->bytes_per_row[0];
+  bytes_per_blocklines[1] = priv->bytes_per_row[1]/2;
+  bytes_per_blocklines[2] = priv->bytes_per_row[2]/2;
   bytes_per_mcu[0] = 8;
   bytes_per_mcu[1] = 4;
   bytes_per_mcu[2] = 4;
diff --git a/com32/lib/sys/vesa/background.c b/com32/lib/sys/vesa/background.c
index 026cbc7..64a4604 100644
--- a/com32/lib/sys/vesa/background.c
+++ b/com32/lib/sys/vesa/background.c
@@ -160,10 +160,8 @@ static int read_jpeg_file(FILE *fp, uint8_t *header, int len)
   size_t length_of_file = filesize(fp);
   unsigned int width, height;
   int rv = -1;
-  unsigned char *components[3], *in_row_ptr;
-  uint32_t *out_row_ptr;
-  int bytes_per_row, copy_bytes;
-  int i;
+  unsigned char *components[1];
+  unsigned int bytes_per_row[1];
 
   jpeg_file = malloc(length_of_file);
   if (!jpeg_file)
@@ -181,28 +179,24 @@ static int read_jpeg_file(FILE *fp, uint8_t *header, int len)
     goto err;
 
   tinyjpeg_get_size(jdec, &width, &height);
-  if (width > 4096 || height > 4096)
+  if (width > VIDEO_X_SIZE || height > VIDEO_Y_SIZE)
     goto err;
 
-  tinyjpeg_decode(jdec, TINYJPEG_FMT_BGRA32);
-  tinyjpeg_get_components(jdec, components);
-
-  bytes_per_row = width << 2;
-  copy_bytes = min(width, (unsigned int)VIDEO_X_SIZE) << 2;
-  in_row_ptr = components[0];
-  out_row_ptr = (uint32_t *)&__vesacon_background[0];
+  components[0] = (void *)&__vesacon_background[0];
+  tinyjpeg_set_components(jdec, components, 1);
+  bytes_per_row[0] = VIDEO_X_SIZE << 2;
+  tinyjpeg_set_bytes_per_row(jdec, bytes_per_row, 1);
 
-  for (i = 0; i < (int)height; i++) {
-    memcpy(out_row_ptr, in_row_ptr, copy_bytes);
-    in_row_ptr += bytes_per_row;
-    out_row_ptr += VIDEO_X_SIZE;
-  }
+  tinyjpeg_decode(jdec, TINYJPEG_FMT_BGRA32);
 
   rv = 0;
 
  err:
+  /* Don't use tinyjpeg_free() here, since we didn't allow tinyjpeg
+     to allocate the frame buffer */
   if (jdec)
-    tinyjpeg_free(jdec);
+    free(jdec);
+
   if (jpeg_file)
     free(jpeg_file);
 
diff --git a/com32/lib/sys/vesa/initvesa.c b/com32/lib/sys/vesa/initvesa.c
index ad551a9..82c9940 100644
--- a/com32/lib/sys/vesa/initvesa.c
+++ b/com32/lib/sys/vesa/initvesa.c
@@ -164,7 +164,7 @@ static int vesacon_set_mode(void)
 
   /* Now set video mode */
   rm.eax.w[0] = 0x4F02;		/* Set SVGA video mode */
-  rm.ebx.w[0] = mode | 0xC000;	/* Don't clear video RAM, use linear fb */
+  rm.ebx.w[0] = mode | 0x4000;	/* Clear video RAM, use linear fb */
   __intcall(0x10, &rm, &rm);
   if ( rm.eax.w[0] != 0x004F ) {
     rm.eax.w[0] = 0x0003;	/* Set regular text mode */
-- 
2.7.4