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 000 4-byte signature: "PXM "
 004 4-byte unsigned long: version number (currently "2")
 008 4-byte unsigned long: version of the emulator used
 00C 1-byte flags:
    bit 0: reserved, set to 0
    bit 1:
          if "0", movie begins from power-on
          if "1", movie begins from an embedded savestate
    bit 2:
          if "0", NTSC timing
          if "1", PAL timing
    bit 3:
          if "0", movie does not contain embedded memory cards
          if "1", movie does contain embedded memory cards
    bit 4:
          if "0", movie does not contain embedded cheat list
          if "1", movie does contain embedded cheat list
    bit 5:
          if "0", movie does not use hacks
          if "1", movie does use hacks such as "SPU/SIO IRQ always enabled"
    other: reserved, set to 0
 00D 1-byte flags: reserved, set to 0
 00E 1-byte unsigned char: controller port 1 type
 00F 1-byte unsigned char: controller port 2 type
 010 4-byte unsigned long: number of frames
 014 4-byte unsigned long: rerecord count
 018 4-byte unsigned long: offset to the savestate inside file
 01C 4-byte unsigned long: offset to the memory card 1 inside file
 020 4-byte unsigned long: offset to the memory card 2 inside file
 024 4-byte unsigned long: offset to the cheat list inside file
 028 4-byte unsigned long: offset to the CD-ROM IDs inside file
 02C 4-byte unsigned long: offset to the controller data inside file
 030 4-byte unsigned long: string length of author name
 034 string: name of the author

! Controller Types

 01 Mouse
 02 Negcon
 03 Konami Gun
 04 Standard
 05 Analog Joystick
 06 Namco Guncon
 07 Analog Controller

! Savestate
After the header comes a compressed savestate. If the movie starts from power-on, the "savestate" is only 4 empty bytes.

! Memory Cards
After the savestate come two compressed memory cards. If the movie starts from a clean power-on, the "memory cards" are only 8 empty bytes (4 for each one).

! Cheat List
After the memory cards comes a compressed cheat list. If the movie doesn't use them, the "cheat list" is only 4 empty bytes.

! CD-ROM IDs
After the cheat list comes the CD-ROM ID chunk:

 000 1-byte char: how many CDs does the movie use
 001 9-byte string for each CD: CD-ROM ID of each CD used

! Controller Data

After the CD-ROM IDs, comes the controller data.

Bytes per Frame

 04 Mouse
 02 Standard
 06 Analog Joystick
 06 Analog Controller

(The other controller types are currently not supported by PCSX.)

There's also an extra byte for control functions like Reset, Open/Close CD case, etc.

So, if the movie uses 2 standard controllers, we know it will use 5 bytes per frame (2 bytes for player 1, 2 bytes for player 2 and 1 byte for control functions).

! Frame Data
The corresponding bytes indicate which buttons are pressed at each frame for each controller.

! Standard Controller

 000 2-byte unsigned short:
    01 00 Select
    02 00 unknown
    04 00 unknown
    08 00 Start
    10 00 Up
    20 00 Right
    40 00 Down
    80 00 Left
    00 01 L2
    00 02 R2
    00 04 L1
    00 08 R1
    00 10 Triangle
    00 20 Circle
    00 40 Cross
    00 80 Square

! Analog Joystick/Controller

 000 2-byte unsigned short: same as standard
 002 1-byte unsigned char: left X
 003 1-byte unsigned char: left Y
 004 1-byte unsigned char: right X
 005 1-byte unsigned char: right Y
(Values are in range 0-255, where 128 is center position.)

! Mouse

 000 2-byte unsigned short: same as standard
 002 1-byte unsigned char: X movement
 003 1-byte unsigned char: Y movement
Note: Values are in range 0-255, where 128 is center position

(Values are in range 0-255, where 128 is center position.)

! Control Byte

The corresponding bits indicate which functions are used at each frame.

 bit 1: Reset
 bit 2: Open/Close CD case
 bit 3: Enable/Disable "SIO IRQ Always Enabled" hack [4]
 bit 4: Enable/Disable "SPU IRQ Always Enabled" hack [4]
 bit 5: Enable/Disable cheats [5]
 bit 6: Enable/Disable "Resident Evil 2/3 fix" hack [4]
 bit 7: Enable/Disable "Parasite Eve 2 fix" hack[4]

[4]Note: These bits will be ignored at movie playback if the "hacks" header flag is not set.
[5]Note: These bits will be ignored at movie playback if the "cheats" header flag is not set.