hi_vpss_chn_attr

Function

Defines the static attributes of a VPSS physical channel.

Definition

typedef struct {
    hi_bool             mirror_en;
    hi_bool             flip_en;
    hi_vpss_chn_mode    chn_mode;
    hi_u32              width;
    hi_u32              height;
    hi_video_format     video_format;
    hi_pixel_format     pixel_format;
    hi_dynamic_range    dynamic_range;
    hi_compress_mode    compress_mode;
    hi_frame_rate_ctrl  frame_rate;
    hi_u32              depth;
    hi_aspect_ratio     aspect_ratio;
    hi_u32              reserved[10];
} hi_vpss_chn_attr;

For details about basic data types hi_bool and hi_u32, see Basic Data Types.

Members

Member	Description
mirror_en	Reserved (not supported in the current version). Manually set this parameter to 0 to avoid incompatibility with future versions.
flip_en	Reserved (not supported in the current version). Manually set this parameter to 0 to avoid incompatibility with future versions.
chn_mode	Channel working mode. For details, see hi_vpss_chn_mode.
width	Width of the target image. When the VPSS group ID is within the range of [0, 256), both channel 0 and channel 1 support upscaling and downscaling. When the VPSS group ID is within the range of [256, 264), different channels support different functions and have different restrictions as follows: Channel 0 supports only upscaling, up to 16x upscaling. If the width of the image before resizing is less than 4096 pixels, the output width cannot exceed 8192 pixels. If the width of the image before resizing exceeds 4096 pixels, up to 2x upscaling is allowed. Channel 1 supports only downscaling, a maximum of 15x downscaling.
height	Height of the target image. When the VPSS group ID is within the range of [0, 256), both channel 0 and channel 1 support upscaling and downscaling. When the VPSS group ID is within the range of [256, 264), different channels support different functions and have different restrictions as follows: Channel 0 supports only upscaling, up to 16x upscaling. Channel 1 supports only downscaling, a maximum of 15x downscaling.
video_format	Video format. Only HI_VIDEO_FORMAT_LINEAR is supported. For details, see hi_video_format.
pixel_format	Pixel format of the target image. For details, see hi_pixel_format. When the VPSS group ID is within the range of [0, 256). The following formats are supported: HI_PIXEL_FORMAT_YVU_SEMIPLANAR_420 and HI_PIXEL_FORMAT_YUV_SEMIPLANAR_420 If fisheye correction is enabled, only HI_PIXEL_FORMAT_YVU_SEMIPLANAR_420 is supported. When the VPSS group ID is within the range of [256, 264). The following formats are supported: HI_PIXEL_FORMAT_YVU_SEMIPLANAR_422, HI_PIXEL_FORMAT_YUV_SEMIPLANAR_422, HI_PIXEL_FORMAT_YVU_SEMIPLANAR_420, HI_PIXEL_FORMAT_YUV_SEMIPLANAR_420 and HI_PIXEL_FORMAT_YUV_400. If fisheye correction is enabled, HI_PIXEL_FORMAT_YVU_SEMIPLANAR_422, HI_PIXEL_FORMAT_YUV_SEMIPLANAR_422, and HI_PIXEL_FORMAT_YUV_SEMIPLANAR_420 are not supported. Semi-planar 422-to-semi-planar 420 conversion is supported. UV inversion can be implemented by setting the channel output pixel format.
dynamic_range	This is a reserved parameter. For details, see hi_dynamic_range.
compress_mode	Only non-compression HI_COMPRESS_MODE_NONE is supported. For details, see hi_compress_mode.
frame_rate	Frame rate control information. For details, see hi_frame_rate_ctrl. If both the source frame rate and target frame rate are –1, the frame rate is not controlled. In auto mode, the frame rate control does not take effect. The target frame rate must be lower than or equal to the source frame rate.
depth	Queue depth of channel frames obtained by users. If the queue length is 0, images cannot be obtained in HI_VPSS_CHN_MODE_USER mode. When the fisheye correction function is enabled, one more image memory resource needs to be allocated. Value range: [0, 8]
aspect_ratio	Aspect ratio parameter. During the processing of the aspect ratio, perform resizing before adding black borders. A larger resizing ratio will prolong processing by the AI processor and may decrease the frame rate. For details, see hi_aspect_ratio. Filling color of the non-video areas after the aspect ratio is enabled. The value cannot be greater than 0xFFFFFF. If the output image needs to be resized according to the aspect ratio, the image size after resizing is the same as the video area size. The resizing ratio cannot exceed that supported by the VPSS. In ASPECT_RATIO_MANUAL mode, the coordinate values must meet the following requirements: X: greater than or equal to 0 and less than the channel image width; Y: greater than or equal to 0 and less than the channel image height; W: greater than or equal to 64 and less than or equal to the channel image width; H: greater than or equal to 64 and less than or equal to the channel image height. The sum of X and W is less than or equal to the channel image width, and the sum of Y and H is less than or equal to the channel image height.
reserved	Reserved. To ensure compatibility in later versions, use the memset structure for resetting and initialization. Do not explicitly access the reserved field in the code.

Parent topic: Video Processing Subsystem (VPSS)