Message ID | 20220701154701.354052-7-jacopo@jmondi.org |
---|---|
State | Superseded, archived |
Headers | show |
Series |
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Related | show |
On Fri, Jul 01, 2022 at 05:46:59PM +0200, Jacopo Mondi wrote: > Re-work the introduction text. > > This might seems arbitrary but the new text provides a bit more context. > > Signed-off-by: Jacopo Mondi <jacopo@jmondi.org> Acked-by: Paul Elder <paul.elder@ideasonboard.com> > --- > src/libcamera/control_ids.yaml | 32 ++++++++++++++++++++++++-------- > 1 file changed, 24 insertions(+), 8 deletions(-) > > diff --git a/src/libcamera/control_ids.yaml b/src/libcamera/control_ids.yaml > index e6676a149795..225377cf9e76 100644 > --- a/src/libcamera/control_ids.yaml > +++ b/src/libcamera/control_ids.yaml > @@ -218,19 +218,35 @@ controls: > The set of ExposureTimeMode modes that are supported by the camera must > have an intersection with the supported set of AnalogueGainMode modes. > > - As it takes a few frames to apply the exposure time, there is a period of > - time between submitting a request with ExposureTimeMode set to Manual > - and the exposure time component of the AE actually being disabled, > - during which the AE algorithm can still update the exposure time. If an > - application is switching from automatic and manual control and wishes > - to eliminate any flicker during the switch, the following procedure is > - recommended. > + Flickerless exposure mode transitions > + > + Applications that transition from ExposureTimeModeAuto to the direct > + control of the exposure time should aim to do so by selecting an > + ExposureTime value as close as possible to the last value computed by > + the auto exposure algorithm in order to avoid any visible flickering. > + > + To select the correct value to use as ExposureTime value, applications > + should accommodate the natural delay in applying controls caused by the > + capture pipeline frame depth. > + > + When switching to manual exposure mode, applications should not > + immediately specify an ExposureTime value in the same request where > + ExposureTimeMode is set to Manual. They should instead wait for the > + first Request where ExposureTimeMode is reported as > + ExposureTimeModeManual in the Request metadata, and use the reported > + ExposureTime to populate the control value in the next Request to be > + queued to the Camera. > + > + The implementation of the auto-exposure algorithm should equally try to > + minimize flickering and when transitioning from manual exposure mode to > + auto exposure use the last value provided by the application as starting > + point. > > 1. Start with ExposureTimeMode set to Auto > > 2. Set ExposureTimeMode to Manual > > - 3. Wait for the first request to be output that has ExposureTimeMode > + 3. Wait for the first completed request that has ExposureTimeMode > set to Manual > > 4. Copy the value reported in ExposureTime into a new request, and > -- > 2.36.1 >
diff --git a/src/libcamera/control_ids.yaml b/src/libcamera/control_ids.yaml index e6676a149795..225377cf9e76 100644 --- a/src/libcamera/control_ids.yaml +++ b/src/libcamera/control_ids.yaml @@ -218,19 +218,35 @@ controls: The set of ExposureTimeMode modes that are supported by the camera must have an intersection with the supported set of AnalogueGainMode modes. - As it takes a few frames to apply the exposure time, there is a period of - time between submitting a request with ExposureTimeMode set to Manual - and the exposure time component of the AE actually being disabled, - during which the AE algorithm can still update the exposure time. If an - application is switching from automatic and manual control and wishes - to eliminate any flicker during the switch, the following procedure is - recommended. + Flickerless exposure mode transitions + + Applications that transition from ExposureTimeModeAuto to the direct + control of the exposure time should aim to do so by selecting an + ExposureTime value as close as possible to the last value computed by + the auto exposure algorithm in order to avoid any visible flickering. + + To select the correct value to use as ExposureTime value, applications + should accommodate the natural delay in applying controls caused by the + capture pipeline frame depth. + + When switching to manual exposure mode, applications should not + immediately specify an ExposureTime value in the same request where + ExposureTimeMode is set to Manual. They should instead wait for the + first Request where ExposureTimeMode is reported as + ExposureTimeModeManual in the Request metadata, and use the reported + ExposureTime to populate the control value in the next Request to be + queued to the Camera. + + The implementation of the auto-exposure algorithm should equally try to + minimize flickering and when transitioning from manual exposure mode to + auto exposure use the last value provided by the application as starting + point. 1. Start with ExposureTimeMode set to Auto 2. Set ExposureTimeMode to Manual - 3. Wait for the first request to be output that has ExposureTimeMode + 3. Wait for the first completed request that has ExposureTimeMode set to Manual 4. Copy the value reported in ExposureTime into a new request, and
Re-work the introduction text. This might seems arbitrary but the new text provides a bit more context. Signed-off-by: Jacopo Mondi <jacopo@jmondi.org> --- src/libcamera/control_ids.yaml | 32 ++++++++++++++++++++++++-------- 1 file changed, 24 insertions(+), 8 deletions(-)