Since the principal addition of these formats is to add explicit fields
for supporting the bitmasks for accessing R/G/B/A it seems odd to
see there is code like this which ignores it when the data is uncompressed
by using these hardcoded values :
456 if ((int)compression == BI_RGB) {
457 redMask = 0x7C00;
458 greenMask = 0x3E0;
459 blueMask = 0x1F;
I do see that it seems likely you copied this from the 108/124 case
but I'd like to see some proof that this is correct.
-phil.
On 03/14/2018 03:39 AM, Jayathirth D V wrote:
Hello All,
Please review the following solution in JDK11 :
Bug : https://bugs.openjdk.java.net/browse/JDK-7031957
Webrev : http://cr.openjdk.java.net/~jdv/7031957/webrev.00/
<http://cr.openjdk.java.net/%7Ejdv/7031957/webrev.00/>
_Issue:_ If we try to read any BMP image of DIB header type
BITMAPV2INFOHEADER/ BITMAPV3INFOHEADER, we get IOException mentioning
the BMP image type in not yet implemented.
_Root cause: _ BMPImageReader doesn’t support DIB header types
BITMAPV2INFOHEADER/ BITMAPV3INFOHEADER we support only
BITMAPCOREHEADER, BITMAPINFOHEADER, BITMAPV4HEADER & BITMAPV5HEADER.
_Solution:_ Many other tools like GIMP, Microsoft PowerPoint,
IrfanView support BITMAPV2INFOHEADER & BITMAPV3INFOHEADER format BMP
images. We can consider BITMAPV2INFOHEADER & BITMAPV3INFOHEADER header
types having functionality in between that of BITMAPINFOHEADER &
BITMAPV4HEADER. BITMAPINFOHEADER with type BITFIELDS & extra 4 bytes
for alpha channel or First 56 bytes of BITMAPV4HEADER is nothing but
BITMAPV3INFOHEADER.
To support BITMAPV2INFOHEADER & BITMAPV3INFOHEADER we can use similar
approach of what we are doing while decoding first 56 bytes under
BITMAPV4HEADER. So I have added additional “if()” to do the same, we
can merge decoding of BITMAPV2INFOHEADER & BITMAPV3INFOHEADER at the
same place where we are decoding BITMAPV4HEADER but we need to add
many branch conditions to follow that approach.
Thanks,
Jay
