IMF Application 2e (SMPTE ST 2067-21) offers the option between two sets of JPEG 2000 profiles when performing lossy encoding of UHD video (3840×2160 pixels): Broadcast Contribution Single Tile Profile or 4k IMF Single Tile Lossy Profile.
While Broadcast Contribution Single Tile Profile is sometimes desirable for compatibility with legacy encoders, it also severely limits the maximum sampling rate of the video to 520 MSample/s (1 MSample = 106 samples) at its highest level (Level 5). In contrast, 4k IMF Single Tile Lossy Profile supports sampling rates up to 38400 MSample/s.
The sampling rate of video is calculated according to:
sampling_rate = frame_width_in_pixels × frame_height_in_pixels × frame_rate × average_number_of components_per_pixel
where
average_number_of components_per_pixel = 3 for 4:4:4 R’G’B’ images since there is one R’, one G’ and one B’ value per pixel; and
average_number_of components_per_pixel = 2 for 4:2:2 Y’C’bC’r images since there is two Y’, one C’r and one C’b value per 2 pixels.
As a practical example, 4K UHD 4:4:4 R’G’B’ images at 23.98 fps exceed the capabilities of Broadcast Contribution Single Tile Profile Level 5 since:
sampling_rate = 3840 × 2160 × 24000/1001 × 3 = 596 MSamples/s > 520 MSamples/s
Instead, 4k IMF Single Tile Lossy Profile Main Level 6 Sublevel 3, which has a maximum sampling rate of 1200 MSamples but the same maximum compressed bit rate (800 Mbit/s) as Broadcast Contribution Single Tile Profile Level 5, can be used.
Overall, it is therefore always preferable to use 4k IMF Single Tile Lossy Profile when creating 4K UHD video in IMF Application 2e.