BRIDGE LIVE Video I/O and Streaming Appliance v1.12 81 www.aja.com
you may decide to use an older profile because of compatibility with older
devices (especially older phones).
• GOP size – distance between two I-frames
• B count – number of B-frames between two P-frames
H264 Encoding Options
H.264 is newer than H.262, and it has better image quality and is more efficient.
• Coding – CABAC, CAVLC
• CAVLC is typically used for compatibility with old devices. CAVLC is an older
coding option and is easier to decode. However, for the same bit rate, it
produces lower video quality.
• CABAC is a newer coding option and is a bit harder to decode. It provides
the same quality of video as CAVLC while using 5% to 15% smaller of a bit
rate.
• Profile – Baseline, Main, High
• Similar to H.262 profiles, the higher the profile, the more capabilities it has.
The Main profile and higher allows B frames and CABAC. The High profile
supports 4:2:2 sampling and 10-bit depth.
• GOP size – distance between two I-frames
• B count – number of B-frames between two P-frames
H265 Encoding Options
H.265 supports UltraHD. It is newer and even more efficient than H.264. Its
efficiency is in decoding. (Encoding requires more computing power up front.)
• Profile: Main, Main10
• Main uses 8-bit encoding/decoding. Main 10 uses 10-bit encoding/
decoding. On a system level, 10-bit I/O is more resource intensive.
• GOP size – distance between two I-frames
• B count – number of B-frames between two P-frames
Video Bit Rate
Enter a bit rate to define how much of the total bit rate is dedicated to video data.
You can specify the units in terms of Mbit/s, kbit/s or bit/s.
Scan Rate
BRIDGE LIVE can either keep original frame rates or convert frame rates as
required.
Supported Frame Rate Conversions
BRIDGE LIVE supports frame rate 50% down-conversion capabilities, for example:
• 60p to 30p,
• 59.94 to 29.97,
• 50p to 25p
BRIDGE LIVE also supports frame rate 50% up-conversion, such as:
• 50i to 50p
Frame Rate Conversions Not Supported
However, BRIDGE LIVE does NOT currently support these frame rate conversions:
• 25 to 30,
• 50 to 60,