Tiff to tiff converstion gives size and qaulity difference for final tif in v7.0.7-7 and v6.9.1-0

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jyoti.dash
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Tiff to tiff converstion gives size and qaulity difference for final tif in v7.0.7-7 and v6.9.1-0

Post by jyoti.dash »

When i convert a tif file using the following commnad to tif i get a size and qaulity differnece between the final tiff files between two version of Imagemagick. Can i know what is causing the differnece in size and quality?

Convert.exe -limit area 100mb "C:\Users\Ephesoft\Documents\multipage-pdfCopy-0001.tif" -compress LZW "C:\Users\Ephesoft\Documents\converted-%04d.tif"

example
Original tif fiel szie -181KB
in Version 6.9.1-0 the final tif file size after running the above command is 91KB
in Version 7.0.7-7 the final tif file size after running the above command is 109KB

In some cases the size of a final tif file is smaller in the newer version 7.0.7-7 compared to the final tif size in 6.9.1-0 Which affects the quality of the final tif file.

Can i know how these 2 versions of Imagemagick version is creating a tif of different size and quality even though the command is the same and the oringla file is the same?

snibgo
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Re: Tiff to tiff converstion gives size and qaulity difference for final tif in v7.0.7-7 and v6.9.1-0

Post by snibgo »

Most compression methods for tiff (eg zip and lzw) are lossless, so the quality will be unchanged. Some (eg jpeg) are lossy, so the quality will reduce.

Look at "identify -verbose" for each of the files. What is the compression method of the input and two outputs?
snibgo's IM pages: im.snibgo.com

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