Docs: Add note about YUV420P format with FFMPEG backend on Android

Being a generic format, we can receive either a fully planar 4:2:0 - YUV420P or
a semiplanar NV12/NV21. That will depend on the codec implemented in the device,
so device-dependent.

Fixes: QTBUG-112454
Change-Id: Iebebca8d3d2bb5b540f92ec87b536dcb49ec7e4f
Reviewed-by: Mats Honkamaa <mats.honkamaa@qt.io>
(cherry picked from commit 954053c17cb53b41c8ecf8cb794898c89fdef5e4)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

1 files changed, 17 insertions, 2 deletions

diff --git a/src/multimedia/camera/qcamera.cpp b/src/multimedia/camera/qcamera.cpp
index 928217bd2..ca9200b04 100644
--- a/src/multimedia/camera/qcamera.cpp
+++ b/src/multimedia/camera/qcamera.cpp
@@ -460,6 +460,11 @@ void QCamera::setCameraDevice(const QCameraDevice &cameraDevice)
 
     Gets or sets the currently active camera format.
 
+    \note When using the FFMPEG backend on an Android target device if you request
+    \b YUV420P format, you will receive either a fully planar 4:2:0 YUV420P or a
+    semi-planar NV12/NV21. This depends on the codec implemented by the device
+    OEM.
+
     \sa cameraDevice::videoFormats
 */
 
@@ -468,6 +473,11 @@ void QCamera::setCameraDevice(const QCameraDevice &cameraDevice)
 
     Returns the camera format currently used by the camera.
 
+    \note When using the FFMPEG backend on an Android target device if you request
+    \b YUV420P format, you will receive either a fully planar 4:2:0 YUV420P or a
+    semi-planar NV12/NV21. This depends on the codec implemented by the device
+    OEM.
+
     \sa QCameraDevice::videoFormats
 */
 QCameraFormat QCamera::cameraFormat() const
@@ -477,8 +487,13 @@ QCameraFormat QCamera::cameraFormat() const
 }
 
 /*!
-    Tells the camera to use the format desribed by \a format. This can be used to define
-    as specific resolution and frame rate to be used for recording and image capture.
+    Tells the camera to use the format described by \a format. This can be used to define
+    a specific resolution and frame rate to be used for recording and image capture.
+
+    \note When using the FFMPEG backend on an Android target device if you request
+    \b YUV420P format, you will receive either a fully planar 4:2:0 YUV420P or a
+    semi-planar NV12/NV21. This depends on the codec implemented by the device
+    OEM.
 */
 void QCamera::setCameraFormat(const QCameraFormat &format)
 {