Re: [PATCH 1/3] d3dx9_36: Add support for DIB file in D3DXGetImageInfoFromFileInMemory.

[Alexandre Julliard]

Christian Costa  writes:
> - if (header_size == sizeof(BITMAPINFOHEADER))
> - {
> -
>    BITMAPINFOHEADER *header = (BITMAPINFOHEADER*)*data;
> -
>    ULONG count = header->biClrUsed;
> -
> -
>    if (!count && header->biBitCount <= 8)
> -
>        count = 1 << header->biBitCount;
> -
> -
>    offset = sizeof(BITMAPFILEHEADER) + header_size + sizeof(RGBQUAD) * count;

This isn't correct for all DIB types.

[PATCH 1/3] d3dx9_36: Add support for DIB file in D3DXGetImageInfoFromFileInMemory.

[Christian Costa]

Wich DIB types ? Are you referring to BI_BITFIELDS compression ?

I just looked at windows codecs code and there this code to handle color
masks:

/* if this is a BITMAPINFOHEADER with BI_BITFIELDS compression, we need
to
        read the extra fields */
    if (This->bih.bV5Size == sizeof(BITMAPINFOHEADER) &&
        This->bih.bV5Compression == BI_BITFIELDS)
    {
        This->palette_offset += 12;
    }

For the rest it's the same thing:

/* In a packed DIB, the image follows the palette. */
        ULONG palette_count, palette_size;
        if (This->bih.bV5ClrUsed)
            palette_count = This->bih.bV5ClrUsed;
        else if (This->bih.bV5BitCount <= 8)
            palette_count = 1 << This->bih.bV5BitCount;
        else
            palette_count = 0;
        if (This->bih.bV5Size == sizeof(BITMAPCOREHEADER))
            palette_size = sizeof(RGBTRIPLE) * palette_count;
        else
            palette_size = sizeof(RGBQUAD) * palette_count;
        This->image_offset = This->palette_offset + palette_size;

Albeit windows codecs support also BITMAPCOREHEADER2, BITMAPV4HEADER,
BITMAPV5HEADER the same way as BITMAPINFOHEADER.

Is there still anything wrong ?

Christian

2013/4/22 Alexandre Julliard
> Christian Costa  writes:
> > - if (header_size == sizeof(BITMAPINFOHEADER))
> > - {
> > -
> >    BITMAPINFOHEADER *header = (BITMAPINFOHEADER*)*data;
> > -
> >    ULONG count = header->biClrUsed;
> > -
> > -
> >    if (!count && header->biBitCount <= 8)
> > -
> >        count = 1 << header->biBitCount;
> > -
> > -
> >    offset = sizeof(BITMAPFILEHEADER) + header_size +
>
> sizeof(RGBQUAD) * count;
>
> This isn't correct for all DIB types.
>
> --
> Alexandre Julliard
> [e-mail]