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# Cropping parameter are ignored, or cropping is done but with wrong dimensions
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# Cropping parameters are ignored, or cropping is done but with wrong dimensions
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## The problem
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You merge a video track applying cropping parameters. When you play the file back the video is either unchanged (no cropping applied at all) or the dimensions are wrong.
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You merge a video track applying cropping parameters. When you play the file back, the video is either unchanged (no cropping applied at all) or the dimensions are wrong.
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## Reason
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This is a bug in your player. There's unfortunately no easy way around it.
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In Matroska the cropping parameters are stored as four values (top, left, bottom, right) in the track headers. The video track itself is not modified. It's therefore a lossless process.
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In Matroska, the cropping parameters are stored as four values (top, left, bottom, right) in the track headers. The video track itself is not modified. It's therefore a lossless process.
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During playback it's the player's job to set up video filters properly so that the cropping parameters are honored. The [Matroska spec notes page](http://www.matroska.org/technical/specs/notes.html#Cropping) lists the process to use:
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During playback, it's the player's job to set up video filters properly so that the cropping parameters are honored. The [Matroska spec notes page](http://www.matroska.org/technical/specs/notes.html#Cropping) lists the process to use:
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> PixelXXX (size of the coded image) -> PixelCropXXX (size of the image to keep) -> DisplayXXX (resized cropped image)
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