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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Code snippet:<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>#define RGB16 PIX_FMT_RGB48LE // little endian<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>#define RGB PIX_FMT_BGR24<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>#define YUV422 PIX_FMT_YUV422P10LE<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>#define YUV444 PIX_FMT_YUV444P16LE<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>void Rescaler ( uint8_t* input_data, AVPicture* outp, int in_width, int in_height, PixelFormat in_pix_fmt, int out_width, int out_height, PixelFormat out_pix_fmt)<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> {<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>//initialize context and buffers<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> swsContext = sws_getContext(in_width, in_height, in_pix_fmt, <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> out_width, out_height, out_pix_fmt, SWS_BICUBIC, NULL, NULL, NULL);<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> inp = new AVPicture;<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> memset(inp,0,sizeof(AVPicture));<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> avpicture_fill(inp, input_data, in_pix_fmt, in_width, in_height);<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> memset(outp,0,sizeof(AVPicture));<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> avpicture_alloc(outp, out_pix_fmt, out_width, out_height);<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>//<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> int rc_ht = sws_scale ( swsContext, inp->data, inp->linesize, in_width, in_height, outp->data, outp->linesize);<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> }<o:p></o:p></span></p><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> libav-user-bounces@ffmpeg.org [mailto:libav-user-bounces@ffmpeg.org] <b>On Behalf Of </b>Roman Ryltsov<br><b>Sent:</b> Saturday, January 05, 2013 11:15 AM<br><b>To:</b> This list is about using libavcodec, libavformat, libavutil, libavdevice and libavfilter.<br><b>Subject:</b> Re: [Libav-user] change pixel format without scaling data ? // more 2<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal style='margin-bottom:12.0pt'>Jim,<o:p></o:p></p><div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-right:0in'><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Well, that is my problem – it is not clear how it scales or why if I don’t request it!! What we used to call an ‘undocumented feature’</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>The input to the context is the input format, the input sizes, the output format and the output sizes. Gray levels, scaling, expected means etc. have no part of the context or the input. I would post my code but I am away from the workstation at the moment. But if you look at the function calls for sws_getcontext and sws_scale you will no mention of modifying gray levels.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><o:p> </o:p></p></div></div></blockquote></div><p class=MsoNormal><br><br>A code snippet with your <span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>sws_* </span>calls + values of arguments are worth many words. Post this information here and we will see what is going on.<br><br>Roman<o:p></o:p></p></div></body></html>