Some filename extensions—such as MOV, AVI, MXF, and FLV—denote container file formats rather than denoting a specific audio, video, or image data format. Container files can contain data encoded using various compression and encoding schemes. Adobe Media Encoder can import these container files, but the ability to import the data that they contain is dependent on which codecs (specifically, decoders) are installed.
By installing additional codecs, you can extend the ability of Adobe Media Encoder to import additional file types. Many codecs must be installed into the operating system and work as a component inside the QuickTime or Video for Windows formats. Contact the manufacturer of your hardware or software for more information about codecs that work with the files that your specific devices or applications create.