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Low resolution of Palm leave images on Malayalam Wikisource makes them hard to read
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Description

At Malayalam Wikisource we are trying to transcribe a Palm leaf manuscript using Proofread Page Extension. This is the first time we are working on a Palm leave manuscript in Malayalam Wikisource.

The manuscript that we are working is this commons file https://commons.wikimedia.org/wiki/File:MaI286_highres.pdf

The Malayalam Wikisource Index page for this manuscript is here https://ml.wikisource.org/wiki/Index:MaI286_highres.pdf

When we try to work on a page of this manuscript using the Proofread page extension we found that the resolution of palm leave shown in the right/top window is very low (see the attached image ml-wikisource-palm-leaves.jpg). It is very difficult to read and type using the palm leave image displayed. See the sample page we tried here https://ml.wikisource.org/w/index.php?title=Page:MaI286_highres.pdf/5&action=edit

But the jpg of this palm leave from Commons is quite clear and readable as you can see here https://upload.wikimedia.org/wikipedia/commons/thumb/4/49/MaI286_highres.pdf/page5-2532px-MaI286_highres.pdf.jpg

Could you please help to fix this issue.

Event Timeline

@Shijualex I changed the 'Scan resolution in edit mode' parameter in the Index: page for that particular file (per this edit) which should make the images render at a higher resolution for that particular book.

That is nice. Thanks.

So I guess if we set this value (in Index page) for each manuscript (based on its available high resolution) that solves this issue. If that is what suggested we can close this task.

That is nice. Thanks.

So I guess if we set this value (in Index page) for each manuscript (based on its available high resolution) that solves this issue. If that is what suggested we can close this task.

That's probably fine in the short run... though it would be great if we could determine whether this is a recurring problem for most manuscript/landscape texts.

Pinging @kamholz in case they've also encountered similar issues with Balinese manuscripts.

Aklapper renamed this task from Proofread Page Extension - Malayalam Wikisource - Palm leave images are not readable to Low resolution of Palm leave images on Malayalam Wikisource makes them hard to read.Aug 17 2020, 4:47 PM

I just tested this locally. The issue arises from ProofreadPage's code in getImageWidth. If the width is not set in the index, the default (self::DEFAULT_IMAGE_WIDTH) is 1024. This is presumably meant to avoid excessively large image files, but it's counterproductive in this case.

For the Balinese palm-leaf manuscript work I've been doing, we use the low-res version to start with in order to save bandwidth. Then when the user zooms in far enough, we pull in a higher-res version of the zoomed in region from the Internet Archive original via IIIF. Unfortunately there isn't a reliable and fast IIIF endpoint for Commons yet, so this isn't generalizable.

Change 741125 had a related patch set uploaded (by Inductiveload; author: Inductiveload):

[mediawiki/extensions/ProofreadPage@master] Page edit: adjust image size for landscape images

https://gerrit.wikimedia.org/r/741125

Also note that the OpenSeadragon viewer can now directly load from IIIF sources, so if you know the manifest URL (and it's allowed by CORS) you can set it like this:

mw.hook( 'ext.proofreadpage.osd-viewer-ready' ).add( function ( viewer ) {
    viewer
        .addTiledImage( {
            url: iiif_json_url
        } );
} );

More info: https://www.mediawiki.org/wiki/Extension:Proofread_Page/Page_viewer