For the Digital Video Machine, Digital Binloop and A/V Binloop
MPEG (or MPG) stands for Motion Picture Experts Group, the organization that codified the audio/video compression scheme used in the Digital Video Machine and A/V Binloop. Many encoding systems produce MPG files, but not all MPG files may be played on the Digital Video Machine and Binloop. Many MPG files are designed for playback in a small window on a PC, or for transfer over the internet. These MPG files are generally of very low resolution at slow frame rates.The Digital Video Machine and Binloop are designed to accept MPG files encoded at a resolution of 720 x 480 (NTSC) or 720 x 576 (PAL). They can play MPG files encoded at bit rates up to 15 Megabits per second. Since higher bit rates equate to better picture quality, we encourage you to encode your video at the highest bit rate supported.
How Do I Make an MPG File?
The most important step in creating video for your application is to perform the highest quality MPEG encoding of your source material.
Encoding professional-quality MPEG material is more of an art than a science. The person encoding the material must be experienced and the hardware well-chosen, so users deciding whether or not to encode their material themselves should put a lot of thought into what would best suit their needs.
The quality of encoded video depends upon the quality of the source video, the encoding system used, and the skill of the operator. Although encoding your own video is very cost effective and surprisingly straightforward, only an experienced individual can create the highest-quality MPEG. Video material encoded without regard to bleeding colors and motion artifacts will include them, so it is important for the user to decide whether these elements are acceptable. A good alternative to hiring an on-staff MPEG expert (or becoming one yourself) is to hire an experienced post-production house to encode and format your video for you. All you have to do is to provide a Digital Betacam or D-1 master and they do the rest!
Digital Video Machine, Digital Binloop and A/V Binloop MPG Encoding Parameters
- Encoded files must comply to ISO/IEC Specification 13818-2
- MPEG2 files must be encoded as a Program Stream.
- Elementary Video stream must be Main Profile Main Level MP@ML 4:2:0.
- Elementary Audio Stream must also be included and must be AC3 or MPEG1 layer II encoded. Bitrates of 192, 224, or 384 kbps are supported.
- Source audio before encoding is 16 bit at 48 or 44.1 kHz sample rate.
- The two main resolutions supported are 704 x 480 x 29.97 (NTSC) and 704 x 576 x 25 (PAL)
- Maximum Program Stream bitrate is 15Mbps.
- Constant Bitrate (CBR) or Variable Bitrate (VBR)
- Group of Picture (GOP) Structure is CLOSED.
- Normally 13 or 15 frames / GOP.
- I B & P frames will provide the most efficient compression.
- Preferably each GOP will contain a sequence header.