<html> <head> <meta http-equiv="content-type" content="text/html; charset=utf-8"> </head> <body bgcolor="#FFFFFF" text="#000000"> <meta http-equiv="content-type" content="text/html; charset=utf-8"> My real application records live video and uses x264enc to encode it. The compression is 'a bit too aggressive' for my liking. I have written a program to convert a short video using x264enc to encode it so that I can compare the result using different levels of compression – (both video quality and file size). I have read elsewhere that “The range of the quantizer scale is 0-51: where 0 is lossless, 23 is default, and 51 is worst possible. A lower value is a higher quality and a subjectively sane range is 18-28. Consider 18 to be visually lossless or nearly so” and that “increasing the CRF value +6 is roughly half the bitrate while -6 is roughly twice the bitrate ”. I notice from gst-inspect that the x264enc plugin has a property “quantizer” (Constant quantizer or quality to apply … Unsigned integer. Range: 1-50 Default:21) I converted a 4 minute video using the default settings and the output file size was 31.4 MiB. I then changed the value of the quantizer using this line g_object_set (G_OBJECT (videnc), "quantizer", 18, NULL); and ran the program again. This time the file size was 31.4 MiB – so no change. I would have expected the file to be somewhat larger. So, <ul> <li> did I not actually change the property (I did not see any indication that the line had failed) </li> <li> should I have changed something else (as well) </li> <li> should I have done it differently </li> <li> does x264enc ignore that property </li> </ul> <title></title> <meta name="generator" content="LibreOffice 5.0.2.2 (Windows)"> <style type="text/css"> @page { margin: 2cm } p { margin-bottom: 0.25cm; line-height: 120% } </style> <div class="moz-signature"> </div> </body> </html>