[IDEA] Thumbnail Image Quality

[Tim Curtis]

Hi,

If you know some Linux SSH try modifying the code block below for pixel ratio == 2 in the file /var/www/command/thmcache.php, then regenerate the thumbnail cache. If you find a combination of width and quality that improves your covers then post the settings.

$thm_w is the width of the thumbnail image
$thm_q is the jpeg quality factor which ranges from 0 (worst quality, smaller file) to 100 (best quality, biggest file). The default is the default IJG quality value (about 75).

The approach used in thmcache.php for higher resolution thumbnails is to find an image size and quality setting that produces an acceptable image while minimizing file size. The need to minimize file size is present because populating the Album Cover panel is an I-O intensive operation. Smaller files = faster performance.

Code:

if ($pixel_ratio == 2 && $hires_thm == 'Yes') {
    $thm_w = 200;
    $thm_q = 75;
}
elseif ($pixel_ratio >= 3 && $hires_thm == 'Yes') {
    $thm_w = 400;
    $thm_q = 50;
}
else {
    $thm_w = 100;
    $thm_q = 75;
}

-Tim