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Before you can watch movie downloads on your PSP, you need to understand the folder structure, file types, and naming conventions. The PSP does not play standard formats like wmv or Quick Time mov files. It uses MPEG-4 codecs and its own file naming convention to make things a bit more complicated. Once you understand these basics, you’ll be well on your way to downloading any movies, music, games, and more you love on your PSP.
When the PSP was first released, it only supported one movie format: the MPEG-4 SP standard. However, with later updates, the higher AVC format (also known as H.264 or MPEG-4 Part 10) can also be played on the PSP.
MPEG-4 AAC files.
This is the default format initially used for the PSP. It is better known as MPEG-4 Simple Profile, or as MPEG-4 Part 2 and MPEG-4 AAC.
MPEG-4 AAC movies must be placed in the MP_ROOT100MNV01 folder and must be named with an M4V prefix followed by a random number, like this; M4V00001, M4V00002, M4V00003, etc., with .MP4 extension.
When you browse your movie list on your PSP, this type of file will show up with an MPG4 tag.
MPEG-4 AVC (Advanced Video Coding) files.
This format can be played on the PSP after installing firmware update 2.0 or later. AVC files are also known as MPEG-4 Part 10, or more commonly H.264.
AVC files are of a higher quality than standard MPEG-4 files, and are actually a variant of the same format used for great movies on UMD Video discs.
MPEG-4 AVC movies must be placed in the MP_ROOT100ANV01 folder and must be named with a MAQ prefix followed by a random 5-digit number like this, MAQ00001, MAQ00002, MAQ00003, etc., with an .MP4 extension.
When you browse your movie list on your PSP, this type of file will show up with an AVC tag.
Important notes
Using lower case will mean that your PSP will not recognize the file at all. Always remember which folder to put your movie type in and which naming convention to use, so you should name all files using UPPER CASE only.