1. Code samples
2. Codecs
3. JPEG format

Recompress JPEG partially

JPG Lossless JPEG Read Write Filesystem Pipeline

Applies mosaic effect on region of image with partial JPEG recompression.

Сode Snippet

var rect = new System.Drawing.Rectangle(264, 192, 264, 184);

using (var patchBitmap = new Bitmap())
{
    // Apply crop and mosaic transfroms
    using (var reader = ImageReader.Create("Chicago.jpg"))
    using (var crop = new Crop(rect))
    using (var mosaic = new Mosaic(10, 10))
    {
        Pipeline.Run(reader + crop + mosaic + patchBitmap);
    }

    // Patch JPEG
    using (var losslessJpeg = new LosslessJpeg("Chicago.jpg"))
    {
        rect = losslessJpeg.AlignToMCUSize(rect, JpegAlignToSampleSizeMode.Patch);
        losslessJpeg.WritePatched("ResompressJpegPartially.jpg", rect.Location, patchBitmap);
    }
}

Input

Output

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