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9.5.45 — VBR quality and max QP are settable

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@github-actions github-actions released this 29 Jul 08:38
· 26 commits to main since this release
v9.5.45
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9.5.45 — VBR quality and max QP are settable

Splits the rate-control options apart and makes both encoder numbers adjustable, with explanations on the page itself. Default stays CBR, so nothing changes unless you choose otherwise.

Rate Control    CBR  |  VBR
VBR Quality     0 ── 13          (default 6)
VBR Max QP      0 ── 52          (default 40 *)

Both sliders grey out and are skipped in navigation under CBR, where neither means anything.

What the settings mean

Rate Control — CBR or VBR

CBR spends your chosen bitrate evenly, whatever is on screen. An open-sky pass costs exactly as much as a low pass through canopy. So file size is fixed and quality dips on busy scenes — worst precisely where you want detail most.

VBR treats the bitrate as a ceiling and spends it where the picture is complex. Quality is steadier, files are smaller, and write peaks are higher.

bitrate quality file size
CBR constant varies predictable
VBR varies steady content-dependent

VBR Quality (0–13, default 6)

The encoder's own quality target. The scale is undocumented — even its direction — which is why the full range is exposed rather than a couple of presets. Finding where it should sit is what the comparison is for.

VBR Max QP (0–52, default 40, marked *)

The quality floor: the worst QP the encoder may fall back to in order to stay under the bitrate ceiling.

  • Lower → better worst-case picture, but the ceiling is hit more often, so files grow
  • Higher → smaller files, but the encoder is free to let busy scenes degrade further

Stock is 52, the worst QP H.264 permits — under VBR that is effectively no floor at all, which is why simply enabling VBR without setting this would have made footage worse. 40 is a suggested starting point, not a measured optimum. That is precisely why it is now adjustable rather than hardcoded.

Why this replaces 9.5.44's layout

9.5.44 packed both choices into one row — CBR / VBR 2 / VBR 6 / VBR 10. That was the same mistake as folding when and how into a single VTX Sent option: they are independent choices, and three fixed points cannot locate a value in a scale the encoder never documented.

Your existing setting is migrated. If you set VBR 2, 6 or 10 in 9.5.43/44, you keep VBR at that quality rather than being reverted to CBR.

Costs, unchanged

  • No extra processing. Encoding runs on the Allwinner video engine; rate control is a parameter to that silicon, not a software path
  • Higher write peaks. VBR exceeds the average on hard scenes by design — smaller files does not mean easier on the card
  • Less predictable capacity. CBR's fixed MB/min is genuinely useful in a flight recorder

Useful report if you fly it: which Quality and Max QP, whether it looked better or worse than CBR, and the file size for a comparable clip. The direction of the quality scale is the one thing that cannot be determined from the source.

Files

File Size (bytes) MD5
HDZERO_GOGGLE-77-206-9.5.45.bin 9973760 9060b3548f5c4231f1bc713796dfa937
HDZERO_GOGGLE2-77-184-9.5.45.bin 12892160 abb7336e2b9f4317790309eb7d7f9f65
HDZERO_BOXPRO-77-211-9.5.45.bin 9676800 9063c371b756abddfd1a909d12e302ec

Copy the .bin for your model to the SD card root, then Menu → Firmware → Update Goggle.

Record OSD remains unfixed — see 9.5.42.

Assets 5
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