Common issues and solutions for media processing in ApsaraVideo VOD.
How do I upload videos without transcoding them?
Use the No Transcoding template, which is a special transcoding template supported by ApsaraVideo VOD, to upload videos without transcoding. ApsaraVideo VOD writes file information to video stream information instead of transcoding the video. When you call the GetPlayInfo operation, the mezzanine file URLs are returned as playback URLs. This template is suited for scenarios that require quick playback, such as short video and live-to-VOD.
Only the following formats support direct playback without transcoding: MP4, FLV, M3U8, MP3, and WEBM.
How do I configure a video to automatically scale in proportion to its original aspect ratio?
When you configure the template output, specify only the width or the height. The other dimension is automatically adjusted to maintain the original aspect ratio.
How do I extract the audio track of a video when the video is transcoded?
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Method 1: Add another transcoding template, set Encapsulation Format to mp4 or hls, and then select Disable Video.
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Method 2: Add another transcoding template and set Encapsulation Format to mp3.
How is conditional transcoding typically used?
Use conditional transcoding when you want to generate streams in higher definitions. For example, if you set the definition to 4K but the mezzanine file resolution is lower than 4K, you can perform one of the following operations:
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Do not transcode videos of the specified specifications.
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Transcode the video but keep the bitrate or resolution of the transcoded stream the same as the mezzanine file.