func: static void do_video_stats(OutputStream *ost,int frame_size) if ( ! vstats_file )  vstats_file = fopen ( vstats_filename , "w" ); if ( ! vstats_file )  fprintf ( vstats_file , "frame= %5d q= %2.1f " , frame_number , ( ( enc -> coded_frame -> quality ) / ( ( float ) 'v' ) ) ); fprintf ( vstats_file , "PSNR= %6.2f " , psnr ( enc -> coded_frame -> error [ 0 ] / ( ( enc -> width * enc -> height ) * 255.0 * 255.0 ) ) ); static double psnr(double d) return - 10.0 * log ( d ) / log ( 10.0 ) ; fprintf ( vstats_file , "f_size= %6d " , frame_size ); fprintf ( vstats_file , "s_size= %8.0fkB time= %0.3f br= %7.1fkbits/s avg_br= %7.1fkbits/s " , ( ( double ) video_size ) / 1024 , ti1 , bitrate , avg_bitrate ); fprintf ( vstats_file , "type= %c\n" , ( av_get_picture_type_char ( enc -> coded_frame -> pict_type ) ) ); 