[Approved] Thumbnails creation fails with "indexed pixel format" exception. (1 Viewer)

[cul8er]

The Picture.cs in the MediaPortal.Util namespace uses some code for creating thumbs that fails on quite a number of images. The error thrown is "a graphics object cannot be created from an image that has an indexed pixel format".

By replacing the current code in the CreateThumbnail methods;

myBitmap = new Bitmap(iWidth, iHeight, aDrawingImage.PixelFormat);         
using (Graphics g = Graphics.FromImage(myBitmap))
{
	g.CompositingQuality = Thumbs.Compositing;
	g.InterpolationMode = Thumbs.Interpolation;
	g.SmoothingMode = Thumbs.Smoothing;
	g.DrawImage(aDrawingImage, new Rectangle(0, 0, iWidth, iHeight));
	myTargetThumb = myBitmap;
}

with this code;

myBitmap = (Bitmap)System.Drawing.Image.FromFile(aInputFilename, true);
Bitmap tmp = new Bitmap(iWidth, iHeight);
using (Graphics g = Graphics.FromImage(tmp))
{
    g.CompositingQuality = Thumbs.Compositing;
    g.InterpolationMode = Thumbs.Interpolation;
    g.SmoothingMode = Thumbs.Smoothing;
    g.DrawImage(myBitmap, new Rectangle(0, 0, iWidth, iHeight));
    myTargetThumb = myBitmap;
}
if (tmp != null)
{
    tmp.SafeDispose();
}

solved the problem and I get many more thumbs downloaded for artists in MP.

best regards
cul8er

 

[chemelli]

re: Thumbnails creation fails with "indexed pixel format" exception.

Evaluating...

Simone

 

[arion_p]

re: Thumbnails creation fails with "indexed pixel format" exception.

I cannot reproduce the issue to test your patch. Can you please provide steps to reproduce and possibly a couple of sample images that exhibit this behaviour?

 

[arion_p]

re: Thumbnails creation fails with "indexed pixel format" exception.

Any news on this one?

 

[cul8er]

re: Thumbnails creation fails with "indexed pixel format" exception.

Hi,

Sorry for no noticing this sooner (thanks for the PM chemelli). I will investigate what picture it was that got this error and get back to you in a day or so.

best regards
cul8er

 

[chemelli]

re: Thumbnails creation fails with "indexed pixel format" exception.

can we close this as "unable to reproduce" ?

Simone

 

[cul8er]

re: Thumbnails creation fails with "indexed pixel format" exception.

Hi,

Here is how you can reproduce this error;
1. Have a song with the artist Toto
2. Open MP Configuration
3. Goto Plugins\Audioscrobbler
4. Goto Coverart and press Refresh and in my case I have no thumbs for Artist Toto. I then press Lookup.
5. After the lookup I can see that the image is still missing.

Then Open Configuration.log (I have attached the appropriate part below) and see that the scraper actually found an image and it was downloaded (you can also find that image in the TEMP directory). But the thumb in the Thumbs directory in MP never got that image.

Change the code I suggested and rerun this and the thumb will be generated.

best regards
cul8er

 

[arion_p]

re: Thumbnails creation fails with "indexed pixel format" exception.

Ah, now I see. The problem is not with images with indexed pixel format but with B&W images (the image referred to in your log is a 8-bit B&W JPG and it is kind of rare - usually even B&W images are encoded as color in JPG). Nonetheless this is an issue and should be fixed.

I will take a look at the issue and your patch.

 

[cul8er]

re: Thumbnails creation fails with "indexed pixel format" exception.

Hi,

Thank you. Perhaps I have misinterpreted the C# error message

Please see this for the index error.

The index error is usually received from these images;
PixelFormatUndefined
PixelFormatDontCare
PixelFormat1bppIndexed
PixelFormat4bppIndexed
PixelFormat8bppIndexed
PixelFormat16bppGrayScale
PixelFormat16bppARGB1555

cheers
cul8er

 

[SilentException]

re: Thumbnails creation fails with "indexed pixel format" exception.

So is this patch still valid? arion_p, cul8er?