<div dir="ltr"><br><div class="gmail_extra"><span style="font-family:arial,helvetica,sans-serif"><font>A quick look at your code, you are opening up the encoder each time you write to disk:</font><br><br><font><span lang="EN-US">png_encoder_codec
</span><span lang="EN-US">=</span><span lang="EN-US"> avcodec_find_encoder_by_name (</span><span lang="EN-US">"png"</span><span lang="EN-US">)</span><span lang="EN-US">;<br><br></span></font></span></div><div class="gmail_extra"><font><span style="font-family:arial,helvetica,sans-serif"><span lang="EN-US">Do it just once, like at startup time, and use encoding routines on this </span><br><span lang="EN-US">png_encoder_codec later.<br><br></span></span></font></div><div class="gmail_extra"><span style="font-size:10pt;font-family:Consolas;color:black" lang="EN-US"><font><span style="font-family:arial,helvetica,sans-serif">Hope this helps</span></font><br></span></div></div>