Video Output Options ==================== The video output options mostly control how the .ass subtitles are rendered into video. .. image:: images/video_options.png :alt: Video Options section of the kbp2video UI Background Color ---------------- The "Apply BG" button becomes active when any tracks are selected in the left pane. It replaces the background color or media with the selected color. A color can be typed in via RGB hex code, or can be selected with a color picker by clicking "Choose...". The selected color also doubles as a default for any tracks that do not have a color specified when the conversion is run. Loop background video --------------------- If this is not set and a background video is in use, the video will play exactly once, to its full duration. If the duration is less than the audio, the last frame will repeat until the audio has completed. If this is set, the background video will loop as many times as needed to the duration of the audio (even if that is less than 1, so the background video will be truncated if longer than the audio). Output Resolution ----------------- This sets the resolution of the rendered video. It's editable, so you do not need to use one of the available options. It's also used in the subtitle creation process to set the PlayResX, PlayResY options for the subtitle. See :ref:`subtitle_options:Aspect Ratio` for more details on that. When a background video is used, that is instead used to determine the output resolution (though the subtitle file is still created using the provided resolution). It's highly recommended to set the output resolution to be equal to your background video, or at least have the same aspect ratio. .. -- option was removed from UI Override background ------------------- This feature isn't implemented yet, but when it is, it will allow for scaling and letterboxing the background video/image to the specified output resolution. Until it is available, please make sure your background media is already at the desired resolution. Output File Type ---------------- This is the container type to use for your output file. mp4 is recommended for compatibility. If you need to ship with flac audio, use mkv. Video Codec ----------- The available options depend on the container format chosen. This is nowhere near an exhaustive list of the available codecs ffmpeg can do, but it includes all the best modern ones. For compatibility, h264 is recommended. If you need lossless video, e.g. to reencode or edit further before release, libvpx-vp9 is recommended. Lossless video -------------- Encode losslessly - only recommended if you are going to reencode or edit further. If you have enough bandwidth for it, YouTube will accept lossless uploads though. Video Quality ------------- If lossless is not selected, you can set the CRF quality value for the video. The default of 23 is usually a good choice for h264. Left of that is lower quality and right is higher. The slider goes from 40-10 (CRF scale is reversed with tick marks at the 5 increments). For other codecs, the same quality as h264 can be achieved with worse quality values (higher CRF). Roughly 28-30 are likely to be good default values for them. If you have a similar format for all your videos, it may be a good idea to convert a video at a few different levels to determine what works best for you in terms of quality vs size and use that value going forward. You may also consider slightly higher quality video for what you upload to YouTube, because they are going to recompress it. Audio Codec ----------- Available options depend on the container format. aac is recommended here for compatibility unless you want lossless audio, in which case use flac. Audio Bitrate ------------- Has no effect if using flac. The default is 256k, which should be more than enough for aac. Feel free to adjust if you'd like.