Access ImageParams during pipeline - such as size and pixelformat

I am currently working on splitting up several pipelines and centralizing redundant code in commands. My problem is that I need imageparams for some transforms such as size and pixelformat of the current image at the runtime of the pipeline. The steps do not know of each other and are not able to access each others parameters, such as (in step 5) "What was the target pixelformat of the colorconversion?".

For example:

1. Start with an image with lots of white all around.

2. Remove the white, it gets smaller.

3. Scale it, dependend on a fixed threshold of imagesize (say double it if larger in any dimension than (100, 200)). Obviously I cannot use the imageparams from (1) because they are out of date.

4. Convert the colorspace.

5. Imprint a image from an ImageGenerator, which needs a pixelformat. (1) is outdated again. (The previous step may or may not be executed or at an other position in the pipeline.)

6. Write image.

Is there a way to access such image params during the runtime of the pipeline?

Regards,

Sebastian

However, I am unable to achieve the following:

using (var reader = ImageReader.Create("...")) // In place for another pipeline
using (var combiner = new Combiner())
using (var backGroundGenerator = new ImageGenerator(new Size(200, 100), PixelFormat.Format1bppIndexed, RgbColor.Green))
using (var result = new Bitmap())
{
    combiner.TopImage = reader;
    (backGroundGenerator + combiner + result).Run();
}

I get a PixelFormatNotSupportedException. I found no way to either generate the background with a matching pixelformat or convert it back to the pixelformat of the reader after combining (because I found no way to "save the pixelformat).

Please note: The reader is just for simplicity, it is a complete pipeline by itself in my case. I cannot use "reader.Pixelformat".

(Added resize to the code from above.)

I want to fit an image into 50x50 and place it in the middle of a green area with size 'targetSize'.

var targetSize = new Size(200, 100);
using (var reader = ImageReader.Create("..."))
using (var resize = new Resize(new Size(50, 50), ResizeMode.Fit)) // Say it results in 40x50
using (var combiner = new Combiner())
using (var backGroundGenerator = new ImageGenerator(targetSize, PixelFormat.Format32bppCmyk, RgbColor.Green))
using (var result = new Bitmap())
{
    combiner.Mode=CombineMode.Alpha;
    combiner.OnInit += (sender, e) =>
        {
            // e.ImageParams is from the background, but where are the ImageParams of the TopImage?

            //positioning stuff here
        };

    combiner.TopImage = reader + resize;
    (backGroundGenerator + combiner + result).Run();
}

Edited by user Monday, June 26, 2017 5:42:34 AM(UTC)  | Reason: Explicit question