Decode ICO file manually Hi to all. Currently I am trying to decode ICO file with my own loader, but I am getting weird results. Here is screen from debugger. I have icon 170*170 px, with 32bit color, but in header info I see that height is twice bigger. It will be ok if image size also correspond to the size, but It does not. 170*170*4 = 115 600 170*340*4 = 231 200 But image size is 119 680. After I read 115 600, there are 4080 bytes array, which is mostly filled with zeroes. If I understood correctly, this is transparency buffer. I applied it, but in any case colors does not change. Here is how I read colors data: int realBitsCount = (int)iconImageInfo.Header.bitCount; bool hasAndMask = /*(realBitsCount < 32) &&*/ (height != iconImageInfo.Header.height); dataPtr = IntPtr.Add(dataPtr, Marshal.SizeOf()); var buffer = new byte[width * height * 4]; var stream = new UnmanagedMemoryStream((byte*)dataPtr, iconInfo.BytesInRes); var sizeinBytes = realBitsCount / 8; int bufferOffset = 0; if (realBitsCount == 32) { for (int i = 0; i < buffer.Length; i += sizeinBytes) { stream.Read(buffer, bufferOffset, sizeinBytes); Utilities.Swap(ref buffer[bufferOffset], ref buffer[bufferOffset + 2]); bufferOffset += sizeinBytes; } } and here is how I read and apply transparency: int shift; int shift2; byte bit; int mask; int boundary = width * realBitsCount; //!!! 32 bit boundary (http://bit.ly/2LF9FNK) while (boundary % 32 != 0) boundary++; boundary = width; while (boundary % 32 != 0) boundary++; var bufSize = iconInfo.BytesInRes - (width * height * (realBitsCount / 8)); var transparencyBuffer = new byte[bufSize]; stream.Read(transparencyBuffer, 0, (int)bufSize); for (int y = 0; y < height; y++) { for (int x = 0; x < width; x++) { shift = 4 * (x + y * width) + 3; bit = (byte)(7 - (x % 8)); shift2 = (x + (height - y - 1) * boundary) / 8; var b = transparencyBuffer[shift2]; mask = (0x01 & (b >> bit)); var before = buffer[shift]; buffer[shift] *= (byte)(1 - mask); } } And here is what I receive and what I should receive (from left to right) Does anyone know what I am doing wrong here? Please, help me. https://ift.tt/eA8V8J

Hi to all. Currently I am trying to decode ICO file with my own loader, but I am getting weird results. Here is screen from debugger. I have icon 170*170 px, with 32bit color, but in header info I see that height is twice bigger. It will be ok if image size also correspond to the size, but It does not. 170*170*4 = 115 600 170*340*4 = 231 200 But image size is 119 680. After I read 115 600, there are 4080 bytes array, which is mostly filled with zeroes. If I understood correctly, this is transparency buffer. I applied it, but in any case colors does not change. Here is how I read colors data: int realBitsCount = (int)iconImageInfo.Header.bitCount; bool hasAndMask = /*(realBitsCount < 32) &&*/ (height != iconImageInfo.Header.height); dataPtr = IntPtr.Add(dataPtr, Marshal.SizeOf<IconImageInfo>()); var buffer = new byte[width * height * 4]; var stream = new UnmanagedMemoryStream((byte*)dataPtr, iconInfo.BytesInRes); var sizeinBytes = realBitsCount / 8; int bufferOffset = 0; if (realBitsCount == 32) { for (int i = 0; i < buffer.Length; i += sizeinBytes) { stream.Read(buffer, bufferOffset, sizeinBytes); Utilities.Swap(ref buffer[bufferOffset], ref buffer[bufferOffset + 2]); bufferOffset += sizeinBytes; } } and here is how I read and apply transparency: int shift; int shift2; byte bit; int mask; int boundary = width * realBitsCount; //!!! 32 bit boundary (http://bit.ly/2LF9FNK) while (boundary % 32 != 0) boundary++; boundary = width; while (boundary % 32 != 0) boundary++; var bufSize = iconInfo.BytesInRes - (width * height * (realBitsCount / 8)); var transparencyBuffer = new byte[bufSize]; stream.Read(transparencyBuffer, 0, (int)bufSize); for (int y = 0; y < height; y++) { for (int x = 0; x < width; x++) { shift = 4 * (x + y * width) + 3; bit = (byte)(7 - (x % 8)); shift2 = (x + (height - y - 1) * boundary) / 8; var b = transparencyBuffer[shift2]; mask = (0x01 & (b >> bit)); var before = buffer[shift]; buffer[shift] *= (byte)(1 - mask); } } And here is what I receive and what I should receive (from left to right) Does anyone know what I am doing wrong here? Please, help me.

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