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Modifying FFmpeg Format Options inside CINELERRA-GG

There are thousands of options for using ffmpeg. Now it is possible to view the available options for a particular video and audio choice by using the wrench icon and then clicking on the view box. FFmpeg has to be the selected file format for this feature to be visible. It makes it a lot easier since only the applicable options show up as opposed to everything that ffmpeg can do. These options are just Hints and some may be missing due to the way that ffmpeg options are coded – CINELERRA-GG shows the option data ffmpeg has exposed.

As an example, instead of reading the entire 264 library information, you only have to look at the shown available options. Both the video and the audio are browsable. The options visible in the Audio/Video Preset textbox are the final values which are used when rendering once you have checked OK. For assistance in choosing the options you want, use the view popup to see the objects that go with the selected format tool, highlight the option, modify the parameter value in the box at the top of the Options window based on what you want, and then click apply. Updated parameter values or new parameters will be appended at the bottom. Note that when you highlight an option, a tooltip will show up when available in the lower right hand corner which describes the option. Also note that the Format and Codec types are shown on the top line of the Options window.

Parameters exist in 3 layers: ffmpeg, codec, and an interface layer. You can apply parameters to each layer. The top 2 layers are accessed with the Kind popup menu. The ffmpeg layer is topmost, and is selected as Kind: ffmpeg. It can specify many of the more common parameters, such as the bitrate, quality, and so on. The middle layer is selected as Kind: codec. These options can specialize your choices, and frequently includes presets and profiles useful for coding well known parameter sets, like profile=high422, preset=medium, or tune=film, etc. The interface layer may or may not be available. It is usually accessible only by an opts parameter, like x264-params key=value:key=value:...These options are passed directly to the low level codec library.

With the format button we can access further parameters, called Private Options. A window opens that contains a new view button. More details in the section: Extra “cin_” Options for Render with FFmpeg

Figure 9.2 shows ffmpeg video as the Kind. Note the x264opts (should actually be x264-params now) in the Video Preset window immediately below. There is also the format window with private options.

Figure 9.2: FFmpeg wrench, video preset, view and format options

Figure 9.3 shows ffmpeg video for the Kind. Note the colored tooltip in the lower right hand corner describing the highlighted option. Also note the allowed Range values above the box provided for keyins. There is also the format window with private options.

Figure 9.3: FFmpeg wrench, audio preset, view and format options