Video for Linux Two (V4L2) Driver
i.MX51 EVK Linux Reference Manual
12-6
Freescale Semiconductor
•
3—Horizontal and vertical flip
•
4—90
°
rotation
•
5—90
°
rotation and vertical flip
•
6—90
°
rotation and horizontal flip
•
7—90
°
rotation with horizontal and vertical flip
12.2.2
Use of the V4L2 Output APIs
This section describes a sample V4L2 capture process that uses the V4L2 output APIs. The application
completes the following steps:
1. Sets the capture pixel format and size using IOCTL VIDIOC_S_FMT.
2. Sets the control information using IOCTL VIDIOC_S_CTRL, for rotation.
3. Requests a buffer using IOCTL VIDIOC_REQBUFS. The common V4L2 driver creates a chain
of buffers (currently the maximum number of frames is 3).
4. Memory maps the buffer to its user space.
5. Executes the IOCTL VIDIOC_DQBUF.
6. Passes the data that requires post-processing to the buffer.
7. Queues the buffer using the IOCTL command VIDIOC_QBUF.
8. Starts the stream by executing IOCTL VIDIOC_STREAMON.
9. VIDIOC_STREAMON and VIDIOC_OVERLAY cannot be enabled simultaneously.
12.3
Source Code Structure
lists the source and header files associated with the V4L2 drivers. These files are available in
the following directory:
<ltib_dir>/rpm/BUILD/linux/drivers/media/video/mxc
.
Table 12-1. V2L2 Driver Files
File
Description
capture/mxc_v4l2_capture.c
V4L2 capture device driver
output/mxc_v4l2_output.c
V4L2 output device driver
capture/mxc_v4l2_capture.h
Header file for V4L2 capture device driver
output/mxc_v4l2_output.h
Header file for V4L2 output device driver
capture/ipu_prp_enc.c
Pre-processing encoder driver
capture/ipu_prp_vf_adc.c
Pre-processing view finder (asynchronous) driver
capture/ipu_prp_vf_sdc.c
Pre-processing view finder (synchronous foreground) driver
capture/ipu_prp_vf_sdc_bg.c
Pre-processing view finder (synchronous background) driver
capture/ipu_still.c
Pre-processing still image capture driver
Summary of Contents for i.MX51 EVK
Page 1: ...Part Number 924 76374 Rev 10 11 01 11 2010 i MX51 EVK Linux Reference Manual...
Page 14: ...i MX51 EVK Linux Reference Manual xiv Freescale Semiconductor...
Page 18: ...i MX51 EVK Linux Reference Manual xviii Freescale Semiconductor...
Page 24: ...i MX51 EVK Linux Reference Manual xxiv Freescale Semiconductor...
Page 38: ...Machine Specific Layer MSL i MX51 EVK Linux Reference Manual 2 8 Freescale Semiconductor...
Page 52: ...MC13892 Digitizer Driver i MX51 EVK Linux Reference Manual 5 4 Freescale Semiconductor...
Page 64: ...TV Encoder TVE Driver i MX51 EVK Linux Reference Manual 10 4 Freescale Semiconductor...
Page 82: ...Video for Linux Two V4L2 Driver i MX51 EVK Linux Reference Manual 12 8 Freescale Semiconductor...
Page 86: ...i MX5 Dual Display i MX51 EVK Linux Reference Manual 13 4 Freescale Semiconductor...
Page 100: ...X Windows Acceleration i MX51 EVK Linux Reference Manual 16 6 Freescale Semiconductor...
Page 118: ...Low Level Keypad Driver i MX51 EVK Linux Reference Manual 20 6 Freescale Semiconductor...
Page 134: ...Security Drivers i MX51 EVK Linux Reference Manual 22 10 Freescale Semiconductor...
Page 148: ...Inter IC I2C Driver i MX51 EVK Linux Reference Manual 24 4 Freescale Semiconductor...
Page 178: ...ARC USB Driver i MX51 EVK Linux Reference Manual 29 10 Freescale Semiconductor...
Page 194: ...OProfile i MX51 EVK Linux Reference Manual 33 6 Freescale Semiconductor...