av_register_image_format(&ppm_image_format);
av_register_image_format(&pgmyuv_image_format);
av_register_image_format(&yuv_image_format);
av_register_image_format(&ppm_image_format);
av_register_image_format(&pgmyuv_image_format);
av_register_image_format(&yuv_image_format);