const HELD_KEY_BITS_PER_PIXEL: f64 = 1.6;Expand description
The bits a pixel a held key frame of a constant rate is given at least (held_key_bits):
VCE spends a frame’s budget down the picture and codes the rows it runs out on at its
coarsest, so a key frame short of what the picture needs at the paint-over quality comes
out sharp at the top and smeared below: 1080p text in 0.8 bits a pixel came to 271 kB at
25.5 dB (H.264, 52 dB in the top rows, 18 in the bottom ones) and 307 kB at 39.0 (HEVC), in
1.6 to 463 kB at 51.5 and 380 kB at 47.1. The driver’s best quality level for the key frame
changed nothing.