# Disabling FaceTime HD camera post-processing on macOS

> Source: <https://gist.github.com/breitburg/9e88c6bd500902dfda6662b1dc658a59>
> Published: 2026-10-19 23:18:05+00:00

Tested on a MacBook Pro 14" (M1 Pro), macOS 27.0.1.

```
for k in EnableAppleISPEmulator EnableVEIRL EnableMCTF; do
  sudo -u _cmiodalassistants defaults write com.apple.coremedia $k -bool NO
done
sudo killall appleh13camerad
```

To undo, run the same loop with `defaults delete com.apple.coremedia $k` instead of `write`,
then restart the daemon the same way.

The setting is system-wide, so every app using the built-in camera is affected. Expect more visible noise in low light.

About 3 seconds after the camera opens, the image becomes noticeably smoother and loses detail. A detail metric on the luma plane drops from about 2.0 to 1.1 within one frame. The drop happens at every resolution, and the frame metadata does not show it.

`appleh13camerad` is the daemon that owns the camera ISP. After the ISP, it passes frames
through a software stage called AppleISPEmulator. That stage runs MLVNR, a temporal neural
denoiser on the Neural Engine. Its rate limiter keeps it off while the model warms up, then
turns it on. You can see this in the daemon's log:

```
/usr/bin/log stream --level info --predicate 'process == "appleh13camerad"'

ProcessFrames_MLVNR_IIR_1:  Suppressing algorithm to achieve target frame-rate
ProcessFrames_MLVNR_IIR_1:  Algorithm rate-limit released.
```

The image changes at the second message.

The daemon reads its settings with `CFPreferencesCopyValue` from the `com.apple.coremedia`
domain of its own user, `_cmiodalassistants`. Disassembling `/usr/sbin/appleh13camerad`
shows which keys it reads:

- `EnableAppleISPEmulator` controls the whole emulator stage, including MLVNR. When it is
off, the stream starts without that stage.
- `EnableVEIRL` controls a GPU enhancement in the same stage.
- `EnableMCTF` controls the multi-frame temporal filter.
- `RadialGainEnable` controls lens-shading correction. It is left on.

The daemon reads these keys when it starts, so it needs a restart after the change. Killing it is safe because launchd relaunches it when an app next uses the camera.

After the change, a 15-second stream shows no MLVNR, emulator or Neural Engine activity in the daemon log. The detail metric stays at 4 to 5.5 throughout. It is higher than the original 2.0 because the temporal filter is also off.