cap_iab_set_vector - Linux

Overview

cap_iab_set_vector sets the Intelligent Adaptation Buffer (IAB) vector for a given device. The IAB vector contains parameters that control the IAB’s behavior, such as the maximum number of buffers, the size of each buffer, and the threshold for triggering IAB.

Syntax

cap_iab_set_vector <device> <vector>

Parameters

  • device: The name of the device to set the IAB vector for.
  • vector: The IAB vector to set. The vector consists of a comma-separated list of values, with each value corresponding to a specific IAB parameter. See the Options/Flags section for more details.

Options/Flags

The following options and flags are available:

  • -h, –help: Display a help message and exit.
  • -v, –verbose: Enable verbose output.
  • -d, –debug: Enable debug output.

Vector Parameters

The IAB vector consists of the following parameters:

  • max_num_buffers: The maximum number of buffers to allocate for the IAB.
  • buf_size: The size of each buffer in bytes.
  • min_num_frames: The minimum number of frames that must be buffered before triggering the IAB.
  • max_num_frames: The maximum number of frames that can be buffered before the IAB is flushed.
  • min_size: The minimum size of the buffer before triggering the IAB.
  • max_size: The maximum size of the buffer before the IAB is flushed.
  • threshold: The threshold for triggering the IAB.

Default Values

The default values for the IAB vector parameters are as follows:

  • max_num_buffers: 10
  • buf_size: 512
  • min_num_frames: 0
  • max_num_frames: 0
  • min_size: 0
  • max_size: 0
  • threshold: 0.5

Examples

Setting the IAB vector for a device

cap_iab_set_vector /dev/video0 "10,512,0,0,0,0,0.5"

Getting the IAB vector for a device

cap_iab_get_vector /dev/video0

Common Issues

The following are some common issues that you may encounter when using cap_iab_set_vector:

  • The IAB vector is not set correctly. Make sure that the vector contains valid values and that the device is supported by the driver.
  • The IAB is not triggering. Check the threshold parameter in the IAB vector. The threshold must be set to a non-zero value for the IAB to trigger.
  • The IAB is flushing too often. The IAB may flush too often if the buffer size is too small or the threshold is too low. Try increasing the buffer size or the threshold.
  • The IAB is not flushing at all. The IAB may not flush at all if the buffer size is too large or the threshold is too high. Try decreasing the buffer size or the threshold.

Integration

cap_iab_set_vector can be combined with other commands and tools to achieve more advanced tasks. For example, you can use cap_iab_set_vector to set the IAB vector for a device and then use cap_iab_get_status to monitor the status of the IAB.

Related Commands

  • cap_iab_get_status: Get the status of the IAB for a given device.
  • cap_iab_reset: Reset the IAB for a given device.