0.91 beta 1 - Export to PCX - Bigger filesize with RLE compression?

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masterjp
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0.91 beta 1 - Export to PCX - Bigger filesize with RLE compression?

Post by masterjp » Fri Jun 08, 2018 5:17 pm

I tested the export dialog and selected the pcx format for export.
To test the RLE compression I recognize, that the RLE compression produce bigger files!
Is it correct? I though a picture compression reduce the filesize and do not increase it.

The upper picture shows the picture without RLE compression and the lower picture with RLE compression.

tst.jpg
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Re: 0.91 beta 1 - Export to PCX - Bigger filesize with RLE compression?

Post by cday » Fri Jun 08, 2018 5:40 pm

masterjp wrote:
Fri Jun 08, 2018 5:17 pm
I tested the export dialog and selected the pcx format for export.
To test the RLE compression I recognize, that the RLE compression produce bigger files!
Is it correct? I though a picture compression reduce the filesize and do not increase it.
I think the answer is simply that different types of compression are best suited to different types of image: colour mode (colour, grayscale or black and white) and different types of content: (photograph or line drawing, for example).

In this case RLE compression isn't suited to the complexity of your photo, but it could be very effective for a line drawing.

RLE Compression

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masterjp
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Re: 0.91 beta 1 - Export to PCX - Bigger filesize with RLE compression?

Post by masterjp » Fri Jun 08, 2018 5:48 pm

I thought so, but I was not sure. Thank you.
CPU: Intel i7 8700k | Mainboard: ASUS Z370-F | RAM: 16 GB - DDR4 | SSD: 256 GB | OS: Windows 10 Pro x64 | XN-View 2.44 | XN-View MP 0.91 beta | Adobe Photoshop Elements 15 & Photoshop XXL

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Re: 0.91 beta 1 - Export to PCX - Bigger filesize with RLE compression?

Post by xnview » Sat Jun 09, 2018 7:51 am

yes it's normal. RLE for PCX is not good for photography, only drawing
Pierre.

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