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Fix bmpcodec 16bpp decoding #276

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Jul 17, 2018
Merged

Fix bmpcodec 16bpp decoding #276

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18 changes: 3 additions & 15 deletions src/bitmap.c
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Original file line number Diff line number Diff line change
Expand Up @@ -29,6 +29,7 @@

#include "gdiplus-private.h"
#include "bitmap-private.h"
#include "bmpcodec.h"
#include "graphics-private.h"
#include "metafile-private.h"

Expand Down Expand Up @@ -2086,25 +2087,12 @@ GdipBitmapGetPixel (GpBitmap *bitmap, INT x, INT y, ARGB *color)
case PixelFormat16bppARGB1555:
case PixelFormat16bppRGB555: {
WORD *scan = (WORD *) v;
WORD pixel = scan[x];

ARGB a = data->pixel_format == PixelFormat16bppARGB1555 ? (pixel & 0x80000000) : 0xFF000000;
BYTE r = (pixel >> 7 & 0xF8) | (pixel >> 12 & 0x07);
BYTE g = (pixel >> 2 & 0xF8) | (pixel >> 6 & 0x07);
BYTE b = (pixel << 3 & 0xF8) | (pixel >> 2 & 0x07);

*color = a | r << 16 | g << 8 | b;
*color = gdip_convert_16bppRGB555_ToARGB (scan[x]);
break;
}
case PixelFormat16bppRGB565: {
WORD *scan = (WORD *) v;
WORD pixel = scan[x];

BYTE r = (pixel >> 8 & 0xF8) | (pixel >> 13 & 0x07);
BYTE g = (pixel >> 3 & 0xFC) | (pixel >> 9 & 0x03);
BYTE b = (pixel << 3 & 0xF8) | (pixel >> 2 & 0x07);

*color = 0xFF000000 | r << 16 | g << 8 | b;
*color = gdip_convert_16bppRGB565_ToARGB (scan[x]);
break;
}
default:
Expand Down
111 changes: 48 additions & 63 deletions src/bmpcodec.c
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Original file line number Diff line number Diff line change
Expand Up @@ -84,8 +84,13 @@ gdip_get_bmp_pixelformat (BITMAPV5HEADER *bih, PixelFormat *dest)
case BI_BITFIELDS:
if (bitCount != 16)
return OutOfMemory;
/* note: incomplete at this stage */
*dest = PixelFormat16bppRGB565;

if ((bih->bV5RedMask == 0x7C00) && (bih->bV5GreenMask == 0x3E0) && (bih->bV5BlueMask == 0x1F))
*dest = PixelFormat16bppRGB555;
else if ((bih->bV5RedMask == 0xF800) && (bih->bV5GreenMask == 0x7E0) && (bih->bV5BlueMask == 0x1F))
*dest = PixelFormat16bppRGB565;
else
*dest = PixelFormat32bppRGB;
break;
default:
switch (bitCount) {
Expand All @@ -99,7 +104,7 @@ gdip_get_bmp_pixelformat (BITMAPV5HEADER *bih, PixelFormat *dest)
*dest = PixelFormat24bppRGB;
break;
case 16:
*dest = PixelFormat16bppRGB565;
*dest = PixelFormat16bppRGB555;
break;
case 8:
*dest = PixelFormat8bppIndexed;
Expand Down Expand Up @@ -313,6 +318,18 @@ gdip_read_bmp_rle_8bit (void *pointer, BYTE *scan0, BOOL upsidedown, int stride,
return Ok;
}

ARGB
gdip_convert_16bppRGB555_ToARGB (WORD pixel)
{
return ((pixel & 0x1F) >> 2) | 8 * ((pixel & 0x1F) | 8 * (((((pixel >> 5) & 0x1F) | (((pixel >> 10) & 0x1C) << 8)) & 0xFFFFFFFC) | 32 * (((pixel >> 5) & 0x1F) | ((((pixel >> 10) & 0x1F) | 0xFFFFFFE0) << 8))));
}

ARGB
gdip_convert_16bppRGB565_ToARGB (WORD pixel)
{
return ((pixel & 0x1F) >> 2) | 8 * ((pixel & 0x1F) | 2 * (((((pixel >> 5) & 0x3F) | (((pixel >> 11) & 0xFFFFFFFC) << 10)) & 0xFFFFFFF0) | ((((pixel >> 5) & 0x3F) | ((((pixel >> 11)) | 0xFFFFFFE0) << 9)) << 6)));
}

static GpStatus
gdip_read_bmp_rle_4bit (void *pointer, BYTE *scan0, BOOL upsidedown, int stride, int scanWidth, int scanCount, ImageSource source)
{
Expand Down Expand Up @@ -686,7 +703,7 @@ gdip_read_BITMAPINFOHEADER (void *pointer, ImageSource source, BITMAPV5HEADER *b
DWORD headerSize = (data_read[3]<<24 | data_read[2]<<16 | data_read[1]<<8 | data_read[0]);
switch (headerSize) {
case BITMAPCOREHEADER_SIZE:
bmi->bV5Size = headerSize;
bmi->bV5Size = headerSize;

/* Old OS/2 format. Width and Height fields are WORDs instead of DWORDS */
dw = 0;
Expand Down Expand Up @@ -784,8 +801,11 @@ gdip_read_BITMAPINFOHEADER (void *pointer, ImageSource source, BITMAPV5HEADER *b
bmi->bV5ClrImportant = (data_read[3]<<24 | data_read[2]<<16 | data_read[1]<<8 | data_read[0]);

/* We've finished reading the BITMAPINFOHEADER but later versions are larger. */
if (bmi->bV5Size == sizeof (BITMAPINFOHEADER))
return Ok;
if (bmi->bV5Size == sizeof (BITMAPINFOHEADER)) {
// A 16bpp BITMAPINFOHEADER BI_BITFIELDS image is followed by a red, green and blue mask.
if (bmi->bV5BitCount != 16 || bmi->bV5Compression != BI_BITFIELDS)
return Ok;
}

dw = 0;
size_read = gdip_read_bmp_data (pointer, data_read, size, source);
Expand All @@ -805,6 +825,9 @@ gdip_read_BITMAPINFOHEADER (void *pointer, ImageSource source, BITMAPV5HEADER *b
return OutOfMemory;
bmi->bV5BlueMask = (data_read[3]<<24 | data_read[2]<<16 | data_read[1]<<8 | data_read[0]);

if (bmi->bV5Size == sizeof (BITMAPINFOHEADER))
return Ok;

dw = 0;
size_read = gdip_read_bmp_data (pointer, data_read, size, source);
if (size_read < size)
Expand Down Expand Up @@ -847,10 +870,6 @@ gdip_read_bmp_image (void *pointer, GpImage **image, ImageSource source)
int loop;
long index;
GpStatus status;
ARGB red_mask = 0;
ARGB green_mask = 0;
ARGB blue_mask = 0;
int red_shift = 0;
unsigned long long int size;

status = gdip_read_BITMAPINFOHEADER (pointer, source, &bmi, &os2format, &upsidedown);
Expand All @@ -865,53 +884,6 @@ gdip_read_bmp_image (void *pointer, GpImage **image, ImageSource source)
goto error;
}

/* for 16bbp images we need to be more precise */
if (format == PixelFormat16bppRGB565) {
/* Newer versions of BITMAPINFOHEADER contains R, G and B masks.*/
if (bmi.bV5Size >= sizeof (BITMAPV3HEADER)) {
red_mask = bmi.bV5RedMask;
green_mask = bmi.bV5GreenMask;
blue_mask = bmi.bV5BlueMask;
} else if (bmi.bV5Size == sizeof (BITMAPINFOHEADER)) {
/* The BITMAPINFOHEADER must be followed by R, G and B masks. */
int size = sizeof (RGBQUAD);
size_read = gdip_read_bmp_data (pointer, (void*)&red_mask, size, source);
if (size_read != size) {
status = OutOfMemory;
goto error;
}
size_read = gdip_read_bmp_data (pointer, (void*)&green_mask, size, source);
if (size_read != size) {
status = OutOfMemory;
goto error;
}
size_read = gdip_read_bmp_data (pointer, (void*)&blue_mask, size, source);
if (size_read != size) {
status = OutOfMemory;
goto error;
}
}

if ((red_mask == 0x7C00) && (green_mask == 0x3E0) && (blue_mask == 0x1F)) {
/* five red bits, five green bits and five blue bits (0x7FFF) */
red_shift = 10;
} else if ((red_mask == 63488) && (green_mask == 2016) && (blue_mask == 31)) {
/* five red bits, six green bits and five blue bits (0xFFFF) */
red_shift = 11;
} else {
red_mask = 0x7C00;
green_mask = 0x3E0;
blue_mask = 0x1F;
red_shift = 10;
}

/* note: CAIRO_FORMAT_RGB16_565 is deprecated so we're promoting the bitmap to 32RGB */
/* why 32bpp when 24 would be enough ? because MS GDI+ loads them as such, but can't display them (empty) */
format = PixelFormat32bppRGB;
/* 16bbp bitmap don't seems reversed like their height indicates */
upsidedown = FALSE;
}

result = gdip_bitmap_new_with_frame (NULL, TRUE);
if (!result) {
status = OutOfMemory;
Expand Down Expand Up @@ -1071,17 +1043,30 @@ gdip_read_bmp_image (void *pointer, GpImage **image, ImageSource source)
case 16: {
int src = 0;
int dest = 0;
SHORT *pix = (SHORT*) data_read;
WORD *pixel = (WORD*) data_read;

index = (line * result->active_bitmap->stride);
while (src < loop) {
BYTE r = ((*pix & red_mask) >> (red_shift - 3));
BYTE g = ((*pix & green_mask) >> (red_shift - 8));
BYTE b = (*pix & blue_mask) << 3;
set_pixel_bgra (pixels, index + dest, b, g, r, 0xff);
WORD color = *pixel;
ARGB argb;

if (format == PixelFormat16bppRGB565) {
argb = gdip_convert_16bppRGB565_ToARGB (color);
}
else {
argb = gdip_convert_16bppRGB555_ToARGB (color);
}

BYTE a = (argb & 0xFF000000) >> 24;
BYTE r = (argb & 0x00FF0000) >> 16;
BYTE g = (argb & 0x0000FF00) >> 8;
BYTE b = (argb & 0x000000FF);

set_pixel_bgra (pixels, index + dest, b, g, r, a);

dest += 4;
src += 2;
pix++;
pixel++;
}
continue;
}
Expand Down
4 changes: 4 additions & 0 deletions src/bmpcodec.h
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Original file line number Diff line number Diff line change
Expand Up @@ -67,6 +67,10 @@ GpStatus gdip_save_bmp_image_to_stream_delegate (PutBytesDelegate putBytesFunc,

ImageCodecInfo *gdip_getcodecinfo_bmp () GDIP_INTERNAL;

/* Conversion functions */
ARGB gdip_convert_16bppRGB555_ToARGB (WORD pixel);
ARGB gdip_convert_16bppRGB565_ToARGB (WORD pixel);

/* helper functions / shared with ICOn codec */
GpStatus gdip_read_BITMAPINFOHEADER (void *pointer, ImageSource source, BITMAPV5HEADER *bmi, BOOL *os2format,
BOOL *upsidedown) GDIP_INTERNAL;
Expand Down
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