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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Hello,<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>I have a series of png images. I read them, convert each of them to RGB24, then fill a frame with the data to create a .mov quicktime file. It all works.<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Each png image is about 200K in size. Each image is 1536x856 pixels. This means that uncompressed, each image is about 4MB.<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>My resulting mov file is about 10MB. Clearly, some compression took place. However, if I use the command line ffmpeg to generate the file using<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>ffmpeg -framerate 10 -i image%02d.png -c:v qtrle output.mov<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>then the resulting file is only 1.3Mb. Below is the output from the ffmpeg command. <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>My question: how do I configure libav through the API to also generate such a small, good-quality file?<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Thanks.<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>-Arthur<o:p></o:p></p><p class=MsoNormal>ffmpeg version 3.0 Copyright (c) 2000-2016 the FFmpeg developers<o:p></o:p></p><p class=MsoNormal> built with gcc 4.8 (Ubuntu 4.8.2-19ubuntu1)<o:p></o:p></p><p class=MsoNormal> configuration: --enable-libopenh264<o:p></o:p></p><p class=MsoNormal> libavutil 55. 17.103 / 55. 17.103<o:p></o:p></p><p class=MsoNormal> libavcodec 57. 24.102 / 57. 24.102<o:p></o:p></p><p class=MsoNormal> libavformat 57. 25.100 / 57. 25.100<o:p></o:p></p><p class=MsoNormal> libavdevice 57. 0.101 / 57. 0.101<o:p></o:p></p><p class=MsoNormal> libavfilter 6. 31.100 / 6. 31.100<o:p></o:p></p><p class=MsoNormal> libswscale 4. 0.100 / 4. 0.100<o:p></o:p></p><p class=MsoNormal> libswresample 2. 0.101 / 2. 0.101<o:p></o:p></p><p class=MsoNormal>Input #0, image2, from 'image%02d.png':<o:p></o:p></p><p class=MsoNormal> Duration: 00:00:01.80, start: 0.000000, bitrate: N/A<o:p></o:p></p><p class=MsoNormal> Stream #0:0: Video: png, rgb24(pc), 1536x856, 10 fps, 10 tbr, 10 tbn, 10 tbc<o:p></o:p></p><p class=MsoNormal>Output #0, mov, to 'output.mov':<o:p></o:p></p><p class=MsoNormal> Metadata:<o:p></o:p></p><p class=MsoNormal> encoder : Lavf57.25.100<o:p></o:p></p><p class=MsoNormal> Stream #0:0: Video: qtrle (rle / 0x20656C72), rgb24, 1536x856, q=2-31, 200 kb/s, 10 fps, 10240 tbn, 10 tbc<o:p></o:p></p><p class=MsoNormal> Metadata:<o:p></o:p></p><p class=MsoNormal> encoder : Lavc57.24.102 qtrle<o:p></o:p></p><p class=MsoNormal>Stream mapping:<o:p></o:p></p><p class=MsoNormal> Stream #0:0 -> #0:0 (png (native) -> qtrle (native))<o:p></o:p></p><p class=MsoNormal>Press [q] to stop, [?] for help<o:p></o:p></p><p class=MsoNormal>frame= 18 fps= 17 q=-0.0 Lsize= 1276kB time=00:00:01.80 bitrate=5808.1kbits/s speed=1.72x<o:p></o:p></p><p class=MsoNormal>video:1275kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.064166%<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><o:p> </o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:12.0pt;font-family:"Times New Roman",serif'><o:p> </o:p></span></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>