7.56.1. Name

VIDIOC_SUBDEV_ENUM_FRAME_SIZE - Enumerate media bus frame sizes

7.56.2. Synopsis


int ioctl(int fd, VIDIOC_SUBDEV_ENUM_FRAME_SIZE, struct v4l2_subdev_frame_size_enum * argp)

7.56.3. Arguments


File descriptor returned by open().


Pointer to struct v4l2_subdev_frame_size_enum.

7.56.4. Description

This ioctl allows applications to enumerate all frame sizes supported by a sub-device on the given pad for the given media bus format. Supported formats can be retrieved with the ioctl VIDIOC_SUBDEV_ENUM_MBUS_CODE ioctl.

To enumerate frame sizes applications initialize the pad, which , code and index fields of the struct v4l2_subdev_mbus_code_enum and call the ioctl VIDIOC_SUBDEV_ENUM_FRAME_SIZE ioctl with a pointer to the structure. Drivers fill the minimum and maximum frame sizes or return an EINVAL error code if one of the input parameters is invalid.

Sub-devices that only support discrete frame sizes (such as most sensors) will return one or more frame sizes with identical minimum and maximum values.

Not all possible sizes in given [minimum, maximum] ranges need to be supported. For instance, a scaler that uses a fixed-point scaling ratio might not be able to produce every frame size between the minimum and maximum values. Applications must use the VIDIOC_SUBDEV_S_FMT ioctl to try the sub-device for an exact supported frame size.

Available frame sizes may depend on the current ‘try’ formats at other pads of the sub-device, as well as on the current active links and the current values of V4L2 controls. See ioctl VIDIOC_SUBDEV_G_FMT, VIDIOC_SUBDEV_S_FMT for more information about try formats.

struct v4l2_subdev_frame_size_enum



Number of the format in the enumeration, set by the application.



Pad number as reported by the media controller API.



The media bus format code, as defined in Media Bus Formats.



Minimum frame width, in pixels.



Maximum frame width, in pixels.



Minimum frame height, in pixels.



Maximum frame height, in pixels.



Frame sizes to be enumerated, from enum v4l2_subdev_format_whence.



Reserved for future extensions. Applications and drivers must set the array to zero.

7.56.5. Return Value

On success 0 is returned, on error -1 and the errno variable is set appropriately. The generic error codes are described at the Generic Error Codes chapter.


The struct v4l2_subdev_frame_size_enum pad references a non-existing pad, the code is invalid for the given pad or the index field is out of bounds.