PAL & NTSC
2001-2016
MPEG IMX is a 2001 development of the Digital Betacam format. The digital video compression uses H.262/MPEG-2 Part 2 encoding at higher bit rates than Betacam SX: 30 Mbit/s (6:1 compression), 40 Mbit/s (4:1 compression), or 50 Mbit/s (3.3:1 compression).
Unlike most MPEG-2 encodings, IMX uses intraframe compression. Additionally, in the IMX system, each frame is the same size to make it easier to record onto videotape.
Video recorded in the IMX format conforms to the specifications of the CCIR 601 standard, with eight audio channels and timecode. It does not have an analog audio (cue) track, like Digital Betacam, but one of the audio channels can be used as a CUE track. This format has been standardized in SMPTE 365M and SMPTE 356M as "MPEG D10 streaming".
With the IMX VTR, Sony introduced new technologies including SDTI and e-VTR. SDTI allows audio, video, timecode, and control functions to be transmitted over a single coaxial cable, while e-VTR technology allows the same data to be sent over IP via an Ethernet interface from the VTR itself.
All IMX VTRs can also play Betacam SX tapes, but can only record to IMX cassettes.
Some models, such as the MSW-M2000P/1, can play both Digital Betacam and analog Betacam and Betacam SP cassettes.
A maximum of 60 minutes can be recorded on S tapes and 184 minutes on L tapes in the 525/60 system.
In the 625/50 format, a 184-minute cassette can record 220 minutes. The MPEG IMX and Betacam SX systems were developed as cheaper alternatives to the Digitbeta format.
The format was discontinued in 2016.