53.5. Warp IP Software API
The software includes:
- intel_vvp_warp_driver
- intel_vvp_warp_data
- intel_vvp_warp_mesh
The intel_vvp_warp_driver is the warp IP driver. It provides API for initializing, configuring, and controlling the Warp IP, warp video channel management, and using debug features.
The intel_vvp_warp_data is the software component that generates mesh, cache, and filter coefficient data required by the warp IP. Place generated data in a region of RAM accessed by the warp IP. This location and other necessary parameters are passed to the warp driver.
This component requires transformation mesh in a predefined format as the main input data. It also requires some IP parameters e.g. number of available engines, processing block dimensions, block cache size, single memory bounce setting.
The intel_vvp_warp_mesh is the software component that generates warp meshes for common affine transformations such as translation, rotation, zoom; perspective transformations e.g. keystone and radial distortion (fisheye) and arbitrary warps defined by a set of curves. Meshes are generated in the format required by the intel_vvp_warp_data interface.
You can use this reference software in a number of real-world applications. However, in some more complex cases you might want to use external software to generate transformation mesh. For example, when projecting image onto a complex surface.
You can deploy the software on a Nios V based system. However, because of computational intensity of the mesh and data generating components, Intel recommends an SoC with a dedicated CPU such as an Intel Arria 10 SX device.
intel_vvp_warp_driver
Name | Description |
---|---|
intel_vvp_warp_init_instance | Initialize driver instance |
intel_vvp_warp_create_channel | Create single engine video processing channel |
intel_vvp_warp_create_double_channel | Create dual engine video processing channel |
intel_vvp_warp_create_quad_channel | Create quad engine video processing channel |
intel_vvp_warp_create_easy_warp_channel | Create easy warp video processing channel |
intel_vvp_warp_add_engine_to_channel | Add a warp engine to existing channel |
intel_vvp_warp_free_channel | Free video processing channel |
intel_vvp_warp_configure_channel | Configure video processing channel |
intel_vvp_warp_apply_transform | Apply video transformation |
intel_vvp_warp_bypass | Bypass video processing |
intel_vvp_warp_reset_skip_ram | Reset skip RAM page |
intel_vvp_warp_reset_input_skip_ram | Reset input skip RAM page |
intel_vvp_warp_check_easy_warp_capable | Check if a warp channel can perform Easy warp |
intel_vvp_warp_set_easy_warp | Set easy warp transformation |
intel_vvp_warp_set_output_latency | Set warp output latency |
intel_vvp_warp_get_channel_framebuffer_size | Get total size of the frame buffer RAM required |
intel_vvp_warp_get_debug_register | Get contents of a warp debug register |
intel_vvp_warp_get_input_debug_register | Get contents of a warp input debug register |
intel_vvp_warp_get_output_debug_register | Get contents of a warp output debug register |
intel_vvp_warp_get_engine_debug_register | Get contents of a warp engine debug register |
intel_vvp_warp_get_engine_status | Get current status flags of the warp engine |
intel_vvp_warp_get_output_status | Get current status flags of the warp output |
intel_vvp_warp_init_instance
-
int intel_vvp_warp_init_instance( intel_vvp_warp_instance_t* instance, intel_vvp_warp_base_t base)
- Description
- Initialize intel_vvp_warp driver instance
- Arguments
- instance – pointer to the intel_vvp_warp software driver instance structure
- base – hardware access handler. In a bare metal environments such as Nios II it is defined as 32-bit unsigned integer representing physical address of the intel_vvp_warp IP on the CPU bus.
- Return value
- Zero on success, negative integer otherwise
intel_vvp_warp_create_channel intel_vvp_warp_create_double_channel intel_vvp_warp_create_quad_channel
-
intel_vvp_warp_channel_t* intel_vvp_warp_create_channel(intel_vvp_warp_instance_t *instance, uint32_t input_idx, uint32_t engine_idx, uint32_t output_idx) intel_vvp_warp_channel_t* intel_vvp_warp_create_double_channel(intel_vvp_warp_instance_t *instance, uint32_t input_idx, uint32_t engine1_idx, uint32_t engine2_idx, uint32_t output_idx) intel_vvp_warp_create_quad_channel(intel_vvp_warp_instance_t *instance, uint32_t input_idx, uint32_t output_idx)
- Description
- Create a video processing channel. The functions allocate hardware resources and initialize driver data structures necessary for processing a video stream up to 7680x4320 pixels.
- Arguments
-
instance – pointer to initialized intel_vvp_warp_instance_t structure;
-
input_idx, engine_idx, engine2_idx, ouput_idx – indexes of the warp IP input, engines and output to use in this channel.
You can configure a single warp IP to provide multiple input, output, and processing engine blocks. These blocks are grouped into video processing channels arbitrarily by using index of the block.
The indexes must be in the range 0..num_inputs(num_outputs or num_engines respectively), where you can obtain num_inputs, num_outputs and num_engines through the intel_vvp_warp_instance_t structure after you initialize the driver instance.
- Return value
- Valid pointer to initialized intel_vvp_warp_channel_t structure on success, null pointer otherwise.
intel_vvp_warp_create_easy_warp_channel
-
intel_vvp_warp_channel_t* intel_vvp_warp_create_easy_warp_channel(intel_vvp_warp_instance_t *instance, uint32_t input_idx, uint32_t output_idx)
- Description
- Create an easy warp video processing channel. The functions allocate hardware resources and initialize driver data structures necessary for processing a video stream up to 3840x2160 pixels using easy warp configuration.
- Arguments
-
instance – pointer to initialized intel_vvp_warp_instance_t structure;
-
input_idx, ouput_idx – indexes of the warp IP input and output to use in this channel.
- Return value
- Valid pointer to initialized intel_vvp_warp_channel_t structure on success, null pointer otherwise.
intel_vvp_warp_add_engine_to_channel
-
int intel_vvp_warp_add_engine_to_channel(intel_vvp_warp_channel_t* channel, uint32_t engine_idx)
- Description
-
Add a warp engine to existing channel.
Warp IP allows you to split video processing between multiple engines. This function adds additional engines to already allocated channels and updates driver and channel data structures accordingly
- Arguments
-
instance – pointer to the intel_vvp_warp software driver instance structure
-
engine_idx – indexes of the warp IP engine to add to the channel
- Return value
- Zero on success, negative integer otherwise
intel_vvp_warp_free_channel
-
void intel_vvp_warp_free_channel(intel_vvp_warp_channel_t* channel)
- Description
- Delete video processing channel and release hardware resources and driver data structures allocated for it
- Arguments
- channel – a valid pointer to initialized intel_vvp_warp_channel_t structure
- Return value
- None
intel_vvp_warp_configure_channel
-
int intel_vvp_warp_configure_channel(intel_vvp_warp_channel_t* channel, intel_vvp_warp_channel_config_t* cfg)
- Description
- Configure video processing channel data structures and allocated hardware by providing necessary parameters such as input/output resolutions, frame buffers location etc.
- Arguments
-
channel – a valid pointer to initialized video processing channel;
-
cfg – a valid pointer to initialized intel_vvp_warp_channel_config_t structure.
- Return value
- Zero on success, negative integer otherwise
intel_vvp_warp_apply_transform
-
int intel_vvp_warp_apply_transform(intel_vvp_warp_channel_t* channel, intel_vvp_warp_data_t* data)
- Description
- Start warping video by configuring the channel to use provided warp data coefficients
- Arguments
-
channel – a valid pointer to initialized video processing channel
-
data – a valid pointer to initialized intel_vvp_warp_data_t structure.
- Return value
- Zero on success, negative integer otherwise
intel_vvp_warp_bypass
-
int intel_vvp_warp_bypass(intel_vvp_warp_channel_t* channel, uint32_t bypass, uint32_t skip_ram_page, uint32_t width, uint32_t height
- Description
- Enable or disable video bypass where the input video displays as is without any processing
- Arguments
-
channel – a valid pointer to initialized video processing channel
-
bypass – a nonzero value to enable video bypass, zero to disable
-
skip_ram_page – number of skip ram page to use after enabling or disabling bypass. The software uses the same page number for both input and output blank skip logic.
-
width, height – override output resolution if necessary. Both width and height have to be nonzero. Typically, use to match the input resolution when enabling video bypass.
- Return value
- Zero on success, negative integer otherwise
intel_vvp_warp_reset_skip_ram
-
void intel_vvp_warp_reset_skip_ram(intel_vvp_warp_channel_t* channel, uint32_t skip_ram_page)
- Description
-
Reset skip RAM page setting all values to zero.
Skip RAM pages are programmed as part of intel_vvp_warp_apply_transform(). Some use scenarios may require skip RAM to reset explicitly. This function allows for that
- Arguments
-
channel – a valid pointer to initialized video processing channel
-
skip_ram_page – skip RAM page to reset
- Return value
- None
intel_vvp_warp_reset_input_skip_ram
-
void intel_vvp_warp_reset_skip_ram(intel_vvp_warp_channel_t* channel, uint32_t skip_ram_page)
- Description
-
Reset input skip RAM page setting all values to zero.
Skip RAM pages are programmed as part of intel_vvp_warp_apply_transform(). Some scenarios may require skip RAM to reset explicitly, which this function allows for
- Arguments
-
channel – a valid pointer to initialized video processing channel
skip_ram_page – input skip RAM page to reset
- Return value
- None
intel_vvp_warp_check_easy_warp_capable
-
int intel_vvp_warp_check_easy_warp_capable(intel_vvp_warp_channel_t* channel)
- Description
- Check if the channel can perform easy warp transforms
- Arguments
- channel – a valid pointer to initialized video processing channel
- Return value
- Zero if the channel can perform easy warp transforms, negative integer otherwise
intel_vvp_warp_set_easy_warp
-
int intel_vvp_warp_set_easy_warp (intel_vvp_warp_channel_t* channel, uint32_t easy_warp)
- Description
- Apply an easy warp transformation to the input video
- Arguments
-
channel – a valid pointer to initialized, easy warp capable video processing channel
-
easy_warp – desired easy warp transformation as 32-bit unsigned integer encoded in the following way:
-
31 3 2 1 0 Reserved Mirror Rotation - Bits 1:0 Rotation field can have the following values:
- 00b – no rotation;
- 01b – 90 degrees counter-clockwise rotation
- 10b – 180 degrees rotation
- 11b – 270 degrees counter-clockwise rotation
- Bit 2: mirrors input video if set. If combined with a rotation the mirror is applied first.
- Bits 1:0 Rotation field can have the following values:
- Return value
- Zero on success, negative integer otherwise
intel_vvp_warp_set_output_latency
-
void intel_vvp_warp_set_output_latency (intel_vvp_warp_channel_t* channel, uint32_t clock_offset)
- Description
- Offset the warp output start-of-processing with the start-of-output by the specified number of system clock cycles. For more information, refer to Warp Low Latency.
- Arguments
-
channel – a valid pointer to initialized video processing channel
-
clock_offset – number of system clock cycles by which to offset the output start-of-processing
- Return value
- None
intel_vvp_warp_get_channel_framebuffer_size
-
void intel_vvp_warp_get_channel_framebuffer_size (intel_vvp_warp_channel_t* channel)
- Description
- Get total size of RAM required for the channel frame buffers.
- Arguments
- channel - a valid pointer to initialized video processing channel
- Return
- Size of required RAM in bytes
intel_vvp_warp_get_debug_register
-
uint32_t intel_vvp_warp_get_debug_register (intel_vvp_warp_instance_t* instance, uint32_t reg_offset)
- Description
- Read content of a warp debug and measurement register. Refer to Warp Debug and Measurement Registers.
- Arguments
-
instance – pointer to initialized intel_vvp_warp_instance_t structure
-
reg_offset – zero based register offset. Use the following register offset macros for this argument:
-
Macro Value INTEL_VVP_WARP_DEBUG_MEM_WR_QUEUES0 0 INTEL_VVP_WARP_DEBUG_MEM_WR_QUEUES1 1 INTEL_VVP_WARP_DEBUG_MEM_RD_QUEUES0 2 INTEL_VVP_WARP_DEBUG_MEM_RD_QUEUES1 3 INTEL_VVP_WARP_DEBUG_MEM_RD_CYCLES 8 INTEL_VVP_WARP_DEBUG_MEM_WR_CYCLES 9 INTEL_VVP_WARP_DEBUG_MEM_STALL_CYCLES 10 - Return value
- Current content of the warp debug and measurement register specified by the reg_offset argument
intel_vvp_warp_get_input_debug_register
-
uint32_t intel_vvp_warp_get_input_debug_register (intel_vvp_warp_instance_t* instance, uint32_t input_idx, uint32_t reg_offset)
- Description
- Read content of a warp input debug and measurement register. Refer to Warp Debug and Measurement Registers.
- Arguments
-
instance – pointer to initialized intel_vvp_warp_instance_t structure
-
input_idx – index of the warp IP input to access
-
reg_offset – zero based register offset. Use the following register offset macros for this argument:
-
Macro Value INTEL_VVP_WARP_DEBUG_INPUT_FRAME_COUNT 0 INTEL_VVP_WARP_DEBUG_INPUT_FRAME_PERIOD 1 INTEL_VVP_WARP_DEBUG_INPUT_MEM_WRITES 2 INTEL_VVP_WARP_DEBUG_INPUT_MIPMAP_MEM_WRITES 3 - Return value
- Current content of the warp input debug and measurement register specified by the reg_offset argument
intel_vvp_warp_get_output_debug_register
-
uint32_t intel_vvp_warp_get_output_debug_register (intel_vvp_warp_instance_t* instance, uint32_t output_idx, uint32_t reg_offset)
- Description
- Read content of a warp output debug and measurement register. Refer to Warp Debug and Measurement Registers.
- Arguments
-
instance – pointer to initialized intel_vvp_warp_instance_t structure
-
output_idx – index of the warp IP output to access
-
reg_offset – zero based register offset. Use the following register offset macros for this argument:
-
Macro Value INTEL_VVP_WARP_DEBUG_OUTPUT_FRAME_COUNT 0 INTEL_VVP_WARP_DEBUG_OUTPUT_FRAME_PERIOD 1 - Return value
- Current content of the warp output debug and measurement register specified by the reg_offset argument
intel_vvp_warp_get_engine_debug_register
-
uint32_t intel_vvp_warp_get_engine_debug_register (intel_vvp_warp_instance_t* instance, uint32_t engine_idx, uint32_t reg_offset)
- Description
- Read content of a warp output debug and measurement register. Refer to Warp Debug and Measurement Registers.
- Arguments
-
instance – pointer to initialized intel_vvp_warp_instance_t structure
-
engine_idx – index of the warp IP engine to access
-
reg_offset – zero based register offset. Use the following register offset macros for this argument:
-
Macro Value INTEL_VVP_WARP_DEBUG_ENGINE_FRAME_COUNT 0 INTEL_VVP_WARP_DEBUG_ENGINE_FRAME_PERIOD 1 INTEL_VVP_WARP_DEBUG_ENGINE_BUSY_CYCLES 2 INTEL_VVP_WARP_DEBUG_ENGINE_FRAME_DELAY 3 INTEL_VVP_WARP_DEBUG_ENGINE_RUN_STATUS 4 INTEL_VVP_WARP_DEBUG_ENGINE_CACHE_LOADS 5 - Return value
- Current content of the warp engine debug and measurement register specified by the reg_offset argument
intel_vvp_warp_get_engine_status
-
uint32_t intel_vvp_warp_get_engine_status (intel_vvp_warp_instance_t* instance, uint32_t engine_idx)
- Description
- Get current status flags of a warp engine. Refer to Warp Debug and Measurement Registers.
- Arguments
-
instance – pointer to initialized intel_vvp_warp_instance_t structure
-
engine_idx – index of the warp IP engine to access
- Return value
- Current values of the engine status flags. The flags are in a 32 bit integer.
-
Bit Flag Description 0 Engine failed to complete frame A sticky flag indicating that the engine fails to complete the processing of a frame. The flag is cleared when read.
intel_vvp_warp_get_output_status
-
uint32_t intel_vvp_warp_get_output_status (intel_vvp_warp_instance_t* instance, uint32_t output_idx)
- Description
- Get current status flags of the warp output. Refer to Warp Debug and Measurement Registers.
- Arguments
-
instance – pointer to initialized intel_vvp_warp_instance_t structure
output_idx – index of the warp IP output to access
- Return
- Current values of the output status flags. The flags are in a 32 bit integer.
Bit | Flag | Description |
0 | Output frame has been repeated | A sticky flag indicating that the output frame repeated because the next rendered frame does not complete in time. The IP clears the flag when read. |
Data structures and types
intel_vvp_warp_base_t
- Description
- Platform specific type to perform register read and write operations on the warp IP. In bare metal environments such as a Nios V processor, it is defined as 32-bit unsigned integer representing physical address of the warp IP on the CPU bus
intel_vvp_warp_instance
-
typedef struct intel_vvp_warp_instance { intel_vvp_warp_base_t base; uint32_t num_inputs; uint32_t num_engines; uint32_t num_outputs; } intel_vvp_warp_instance_t;
- Description
- Main data structure of the driver
- Members
-
base – warp IP access handler
num_inputs – number of available warp inputs
num_engines – number of available warp engines
num_outputs – number of available warp outputs
intel_vvp_warp_channel
-
typedef struct intel_vvp_warp_channel { uint32_t in_use; uint32_t idx; struct intel_vvp_warp_instance* instance; uint32_t num_engines; uint32_t ram_addr; } intel_vvp_warp_channel_t
- Description
- Video processing channel resources and parameters structure
- Arguments
- Return value
-
in_use – non-zero value if the channel is allocated and initialized. Zero otherwise.
-
idx – index number of the channel
-
instance – pointer to the parent driver instance the channel belongs to
-
num_engines – number of warp engines for the channel
-
ram_addr - base address of RAM region allocated for the channel frame buffers
intel_vvp_warp_channel_config
-
typedef struct intel_vvp_warp_channel_config { uint32_t ram_addr; intel_vvp_warp_cs_t cs; uint32_t width_input; uint32_t height_input; uint32_t width_output; uint32_t height_output; uint8_t lfr; } intel_vvp_warp_channel_config_t
- Description
- Video processing channel configuration
- Members
-
ram_addr - base address of RAM region allocated for the channel frame buffers
-
cs – video color space. Must be initialized to
- 00b = YUV
- 01b = RGB reduced range
- 10b = RFG full range.
-
width_input, height_input, width_output, height_output – input and output video dimensions
-
lfr – low frame rate fallback. Must be initialized to 0x0
intel_vvp_warp_data
-
typedef struct intel_vvp_warp_data { uint32_t num_engines; const uint8_t* skip_ram_input; const uint8_t* skip_megablock_data; uint32_t skip_ram_page; uint32_t mipmap_level; uint32_t mesh_step; intel_vvp_warp_engine_data_t engine_data[0]; } intel_vvp_warp_data_t;
- Description
- Warp data descriptor
- Members
-
num_engines – data for how many engines this set contains. .
-
skip_ram_input– data for input skip RAM. Generated by the intel_vvp_warp_data library. Refer to Warp Data structure.
-
skip_megablock_data – data for the blank skip logic. Generated by the intel_vvp_warp_data library. See WarpData structure.
-
_kip_ram_page – skip RAM page to use for blank skip logic for this transform. Warp IP provides 2 pages for intput and 2 pages for output blank skip logic. You can keep skip blank data for different transforms and switch between the pages as necessary. When a transform is applied the software uses the same page number for both input and output blank skip logic.
- mipmap_level - maximum mipmap level used by the current transform. Must be in the range of 0..7
- mesh_step - mesh step in pixels used by the current transform. Must be 8 or 16.
-
engine_data – array of intel_vvp_warp_engine_data_t structures containing warp coefficients for each individual engine
intel_vvp_warp_engine_data
-
typedef struct intel_vvp_warp_engine_data { uint32_t mesh_addr; uint32_t mesh_size; uint32_t filter_addr; uint32_t filter_size; uint32_t fetch_addr; uint32_t fetch_size; uint32_t start_h; uint32_t start_v; uint32_t end_h; uint32_t end_v; uint32_t mesh_stride; } intel_vvp_warp_engine_data_t;
- Description
- Warp coefficient descriptor for an individual warp engine
- Members
-
mesh_addr – address of the mesh coefficients in memory
-
mesh_size – size of the mesh coefficients
-
filter_addr – address of the filter coefficients in memory
-
filter_size – size of the filter coefficients
-
fetch_addr – address of the fetch coefficients in memory
-
fetch_size – size of the fetch coefficients
-
start_h, start_v, end_h, end_v – engine processing region. Internally warp engine processes video in 16x8 pixel blocks with the top-left corner being block [0, 0]. The processing region is defined by the start and end block indexes in horizontal and vertical dimensions.
-
mesh_stride – number of warp mesh nodes per mesh data row. (in sets of 4 minus 1). Required mesh stride is calculated by the intel_vvp_warp_data library.
intel_vvp_warp_data
This software component uses transformation mesh in a predefined format to generate mesh, cache, and filter coefficient data required by the warp IP, and blank skip data if supported by the IP configuration.
If two or four engines are available, the software splits workload evenly so that each engine processes a vertical section of the frame. This software component also provides a factory function to create a warp mesh object for the given input and output resolutions and IP configuration.
Name | Description |
---|---|
WarpDataGenerator | Constructor of the intel_vvp_warp_data component |
GenerateData | Generate warp data |
GenerateLatencyParams | Generate recommended minimum latency settings for a given warp |
GetLastErrorCode | Get warning or error code for the most recent call to GenerateData() |
GetErrorString | Get a string describing the error code passed as argument |
Name | Description |
---|---|
GetHwContext | Create object containing warp IP parameters necessary to generate data |
GenerateDriverData | Create and fill in warp data object required by the warp driver |
Name | Description |
---|---|
WarpMesh::Create | Create mesh object sufficient to hold transform data for the given input and output resolutions and IP configuration |
WarpDataGenerator
- WarpDataGenerator
- Description
- Constructs the main object of the intel_vvp_warp_data software component.
- Arguments
- None
- Return value
- None
GenerateData
-
WarpDataPtr GenerateData(const WarpDataContext& ctx, WarpMeshPtr& mesh)
- Description
- Generate warp coefficients using provided transformation mesh, video resolution and necessary IP parameters. If two or four warp engines are available, the workload is split evenly such that each engine processesa vertical section of the image
- Arguments
-
ctx – reference to an instance of WarpDataContext object containing information about video resolution and IP parameters required to generate data
-
mesh – pointer to the transformation mesh
- Return value
- On success the function returns a valid smart pointer to a WarpData object. If in any region of the frame the requested transform exceeds IP limitations such as maximum downscale ratio or block cache size, the region is rendered blank and the corresponding error code is set. You can retrieve the error code using GetLastErrorCode() call.
GenerateLatencyParams
-
WarpLatencyParamsGenerateLatencyParams(const WarpDataContext& ctx, const WarpDataPtr warp_data, uint32_t system_clock, uint32_t video_clock, uint32_t full_height, uint32_t frame_rate)const
- Description
- Generate recommended minimum warp latency settings for a given warp. The generated settings should be used to set up the video pipeline for the low latency processing. Refer to Low Latency.
- Arguments
- ctx– reference to an instance of WarpDataContext object containing information about video resolution and IP parameters required to generate data
-
warp_data– a smart pointer to a valid WarpData object
-
system_clock – system clock frequency
-
video_clock – video clock frequency
-
full_height – full output video height (including vertical blanking)
-
frame_rate – output frame rate
- Return value
-
Initialized WarpLatencyParams object containing recommended minimum latency settings for the given warp
GetLastErrorCode
-
uint32_t GetLastErrorCode()const
- Description
- Return error or warning code for the most recent call to GenerateData(). The software indicates if warp data generation fails or an important condition is detected by setting a numerical error code. Use this function to retrieve the most recent error code.
- Arguments
- None
- Return value
-
Possible return values are:
Table 1149. Return Values Macro Value Description Success 0 Data generated successfully BlockCacheUsageHigh 1 Block cache usage too high. Output might be unstable DataAllocError 2 Unable to allocate memory for the warp data CompressionTooHigh 3 Software detected compression higher than 2:1 BlockCacheFull 4 Requested warp uses up all available block cache FetchLogicError 5 Error detected in the block cache control logic OutOfFetchMem 6 Requested warp requires too many block cache fetches Unknown 7 All other errors
GetErrorString
-
std::string GetErrorString(const uint32_t error_code) const
- Description
- Return string describing the error code obtained with GetLastErrorCode().
- Arguments
- error_code - integral error code value as returned by GetLastErrorCode()
- Return value
- An object of type std::string containing textual description of the error code
Data structures and types
WarpMesh
-
using resolution_t = std::pair<uint32_t, uint32_t>; class WarpMesh { public: static WarpMeshPtr Create(resolution_t& input, resolution_t& output, WarpHwContextPtr hw_ctx); uint32_t GetStep(); uint32_t GetFractBits(); uint32_t GetVNodes(); uint32_t GetHNodes(); uint32_t GetStreams(); mesh_node_t* GetRow(uint32_t v); }
- Description
-
Class containing user-defined transformation mesh.
-
The transformation mesh defines a mapping between the output and input images. Each entry of the mesh (node) represents a position in the output image and contains the relevant x and y coordinates of the input image encoded as 32-bit integers. The step between mesh nodes and number of fractional bits in the 32-bit values are selected by the software based on the input and output resolution. If any of the dimensions exceeds the value of 3840 the software uses 16x16 mesh step with 3 fractional bits otherwise 8x8 mesh with 4 fractional bits is used. The WarpMesh class allows for multiple mesh streams to be encoded. However only single stream mesh is currently supported by the IP. The class automatically manages internal storage for the mesh data
- Members
- Create(resolution_t& input, resolution_t& output, WarpHwContextPtr hw_ctx) – Factory method to create a mesh object.
- Argumenta
-
sinput, output – input and output frame dimensions.
hw_ctx - smart pointer to an instance of WarpHwContext object containing relevant IP parameters
- Returns
-
On success the function returns a valid smart pointer to a WarpMesh object. If requested input or output resolution exceeds current IP settings the null pointer is returned.
uint32_t GetStep() - Returns distance between mesh nodes
uint32_t GetFractBits() – Returns number of fractional bits in 32-bit position values
uint32_t GetVNodes()
uint32_t GetHNodes() - Returns number of vertical/horizontal nodes in the mesh respectively
mesh_node_t* GetRow(uint32_t v) - Returns pointer to the mesh row.Access individual nodes in the row using pointer arithmetic or indexing
mesh_node_t
-
typedef struct mesh_node { int32_t _x; int32_t _y; } mesh_node_t
- Description
- Structure representing individual entry in the mesh
- Members
- _x, _y – coordinates of the input image this node maps to. the IP represents each value by a 32-bit signed integer with the four least significant bits containing fractional part for subpixel precision.
WarpMeshPtr
- using WarpMeshPtr = std::shared_ptr<WarpMesh>
- Description
- Type alias for a smart pointer wrapper around the mesh class
WarpDataContext
-
struct WarpDataContext { WarpDataContext(const WarpHwContextPtr hw, uint32_t wi, uint32_t hi, uint32_t wo, uint32_t ho); }
- Description
- Structure containing image dimensions and IP parameters required to generate data.
- Members
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WarpDataContext(const WarpHwContextPtr hw, uint32_t wi, uint32_t hi, uint32_t wo, uint32_t ho) - Constructor. The constructor uses provided arguments to initialize the data members, which you should not modify.
- Arguments
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hw – smart pointer to an instance of WarpHwContext object containing relevant IP parameters
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wi, hi – input image width and height
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wo, ho – output image width and height
WarpData
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class WarpData { virtual uint32_t _GetEngines() const; virtual const uint8_t* GetSkipRamInputData() const; virtual const uint8_t* GetSkipMegablockData() const; virtual const_WarpEngineData* GetEngineData(const uint32_t engine) const; virtual uint32_t GetLatencyLines() const; virtual uint32_t GetMipmapLevel() const; virtual uint32_t GetMeshStep() const; };
- Description
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Interface class for accessing generated warp coefficients and data
- Members
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GetEngines() – returns the number of warp engine data objects. The value is always less or equal to MAX_ENGINES
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GetSkipRamInputData() – returns pointer to the input skip RAM data
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GetSkipMegablockData() – returns pointer to the skip blank logic data
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GetEngineData() – returns pointers to individual WarpEngineData objects
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GetLatencyLines() – returns latency in image lines of the current transform. This value is used by the GenerateLatencyParams() call to calculate warp latency settings
GetMipmapLevel() – returns maximum mipmap level used by the current transform
GetMeshStep() – returns warp mesh step (8 or 16) used in this data set
WarpEngineData
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class WarpEngineData { virtual uint32_t GetMeshEntries() const; virtual uint32_t GetFilterEntries() const; virtual uint32_t GetFetchEntries() const; virtual const mesh_entry_t* GetMeshData() const; virtual const filter_entry_t* GetFilterData() const; virtual const fetch_entry_t* GetFetchData() const; };
- Description
- Interface class for accessing data coefficients of individual warp engine
- Members
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GetMeshEntries() – returns number of mesh entries in the data block
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GetFilterEntries() – returns number of filter entries in the data block
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GetFetchEntries() – returns number of fetch entries in the data block
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GetMeshData() – returns pointer to the mesh data
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GetFilterData() – returns pointer to the filter data
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GetFetchData() – returns pointer to the fetch data
mesh_entry_t, filter_entry_t, fetch_entry_t
- Description
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Type aliases to use when accessing individual data blocks and calculating block data size in bytes.
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WarpLatencyParams
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struct WarpLatencyParams { uint32_t _output_latency; uint32_t _total_latency; };
- Description
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Structure contains recommended pipeline latency settings for the low latency processing. Refer to Warp IP Latency.
- Members
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_output_latency - the recommended warp output clock offset to be used in intel_vvp_warp_set_output_latency() driver call. The value is in core_clock clock cycles
_total_latency – the recommended minimum offset between the input and output frames. The value is in axi4s_vid_out_0_clock clock cycles
Helper functions
GetHwContext
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WarpHwContextPtr GetHwContext(intel_vvp_warp_channel_t* ch)
- Description
- Create object containing warp IP parameters necessary to generate data. Function uses warp channel driver structure to extract all necessary IP parameters and create object of the type WarpHwContext, required by the GenerateData() call
- Arguments
- ch - valid pointer to initialized intel_vvp_warp_channel_t structure object mesh_set - reference to a set of transformation meshes
- Return value
- On success the function returns a valid smart pointer to a WarpHwContext object. On failure a nullptr object is returned
GenerateDriverData
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WarpDriverDataPtr GenerateDriverData(const WarpDataContext& ctx, const WarpDataPtr user_data, const uint32_t coef_base_address, const uint32_t skip_ram_page)
- Description
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Create and fill in an object of type intel_vvp_warp_data_t required by the warp driver’s method intel_vvp_warp_apply_transform() to apply warp.
- Arguments
- ctx - reference to the WarpDataContext object containing information about video resolution and parameters the IP uses to generate the warp data
- user_data - Warp data as generated by the GenerateData() call
- coef_base_address - base address in the FPGA accessible RAM where the warp is placed.
- skip_ram_page - number of the blank skip ram page to use for this warp
- Return value
- On success the function returns a valid smart pointer to an intel_vvp_warp_data_t object. On failure a nullptr object is returned. Before applying the warp the client must still transfer the warp data to the locations specified in the returned intel_vvp_warp_data_t object
intel_vvp_warp_mesh
This reference software component allows you to generate sample warp meshes for common affine transformations, perspective transformations, radial distortion compensation and arbitrary transforms defined by a set of curves.
The main object of the component is WarpConfigurator. The WarpConfigurator provides the following three types of warp configurations that the host application can use independently.:
In the fixed warp configuration a set of affine transformations such as translation, rotation, scaling, perspective correction as well as radial distortion (fisheye) compensation are configured individually using corresponding API calls.
In the 4x corner configuration affine and perspective transformations are defined using four points positioned in or around the screen area; This configuration also allows to apply radial distortion compensation.
Arbitrary transformation is defined by a set of curves controlled by a fixed number of control points (knots).
Warp meshes are tied to a specific input and output video resolution. The user must set these accordingly before generating a mesh.
Offset, sizes and positions are accepted as absolute values in pixels. To allow for sub-pixel precision floating-point type is used. Internally these parameters normalized to the [0..1] range using current output resolution and kept in this form. The warp automatically fits into the new output resolution if it changes.
Name | Description |
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WarpConfigurator | Constructor of the intel_vvp_warp_mesh component |
SetInputResolution, GetInputResolution | Set or get input image resolution |
SetOutputResolution, GetOutputResolution | Set or get output image resolution |
GenerateMeshFromFixed | Generate mesh using fixed warp configuration |
GenerateMeshFromCorners | Generate mesh using 4x corner warp configuration |
GenerateMeshFromArbitrary | Generate mesh using arbitrary warp configuration |
SetHSize, GetHSize | Set or get horizontal size of the image |
SetVSize, GetVSize | Set or get vertical size of the image |
SetHOffset, GetHOffset | Set or get horizontal offset of the image |
SetVOffset, GetVOffset | Set or get vertical offset of the image |
SetRotate, GetRotate | Set or get rotation angle |
SetHMirror, GetHMirror | Set or get horizontal mirroring |
SetVMirror, GetVMirror | Set or get vertical mirroring |
SetZoom, GetZoom | Set or get zoom factor |
SetHKeystone, GetHKeystone | Set or get horizontal keystone angle |
SetVKeystone, GetVKeystone | Set or get vertical keystone angle |
SetFOV, GetFOV | Set or get field of view |
SetVAxisOffset, GetVAxisOffset | Set or get vertical axis offset |
SetPreRadial, GetPreRadial | Set or get radial distortion compensation parameters |
SetCorner, GetCorner | Set or get corner position |
SetCornerNorm, GetCornerNorm | Set or get normalized corner position |
SetArbitraryKnotsNum, GetArbitraryKnotsNum | Set or get size of the arbitrary control grid |
SetArbitraryKnot, GetArbitraryKnot | Set or get position of arbitrary control knot |
SetArbitraryKnotNorm, GetArbitraryKnotNorm | Set or get normalized position of arbitrary control knot |
SetMaintainRatio, GetMaintainRatio | Set or get maintain aspect ratio setting |
SetShrinkToFit, GetShrinkToFit | Set or get shrink to fit setting |
WarpConfigurator
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WarpConfigurator(WarpHwContextPtr hw_ctx)
- Description
- Constructs the main object of the intel_vvp_warp_mesh software component
- Arguments
- hw_ctx - smart pointer to an instance of WarpHwContext object containing relevant IP parameters
- Return value
- None
SetInputResolution, GetInputResolution, SetOutputResolution, GetOutputResolution
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void SetInputResolution(const uint32_t width, const uint32_t height) void GetInputResolution(uint32_t& width, uint32_t& height) void SetOutputResolution(const uint32_t width, const uint32_t height) void GetOutputResolution(uint32_t& width, uint32_t& height)
- Description
- Set or get input and output image resolution
- Arguments
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width – image width
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height – image height
- Return value
- None
GenerateMeshFromFixed, GenerateMeshFromCorners, GenerateMeshFromArbitrary
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WarpMeshPtr GenerateMeshFromFixed() WarpMeshPtr GenerateMeshFromCorners() WarpMeshPtr GenerateMeshFromArbitrary()
- Description
- Generate transformation mesh using fixed, 4x corners or arbitrary configurations respectively
- Arguments
- None
- Return value
- Smart pointer to the object of the type WarpMesh containing generated transformation mesh (please see intel_vvp_data interface section for the description of WarpMesh)
SetHSize, GetHSize, SetVSize, GetVSize
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void SetHSize(float pixels) float GetHSize() void SetVSize(float pixels) float GetVSize()
- Description
- Set or get horizontal and vertical size of the image, which is equivalent to scaling the image along the horizontal/vertical axis
- Arguments
- pixels – horizontal or vertical size of the image accordingly
- Return value
- horizontal or vertical size of the image accordingly
SetHOffset, GetHOffset, SetVOffset, GetVOffset
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void SetHOffset(float pixels) float GetHOffset() void SetVOffset(float pixels) float GetVOffset()
- Description
- Set or get horizontal and vertical offsets of the image
- Arguments
- pixels – horizontal or vertical offset of the image accordingly
- Return value
- horizontal or vertical offset of the image accordingly
SetRotate, GetRotate
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void SetRotate(float angle) float GetRotate()
- Description
- Set or get rotation angle of the image in degrees. Image is rotated around the center
- Arguments
- angle – rotation angle in degrees
- Return value
- rotation angle in degrees
SetHMirror, GetHMirror, SetVMirror, GetVMirror
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void SetHMirror(bool v) bool GetHMirror() void SetVMirror(bool v) bool GetVMirror()
- Description
- Set or get image mirroring along horizontal and vertical axis accordingly
- Arguments
- v – true to enable mirroring, false to disable
- Return value
- true if mirroring enabled, false otherwise
SetZoom, GetZoom
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void SetZoom(float zoom) float GetZoom()
- Description
- Set or get image zoom value
- Arguments
- zoom – value > 1 to zoom in, < 1 to zoom out
- Return value
- Configured zoom value
SetHKeystone, GetHKeystone, SetVKeystone, GetVKeystone
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void SetHKeystone(float angle) float GetHKeystone() void SetVKeystone(float angle) float GetVKeystone()
- Description
- Set or get horizontal and vertical keystone compensation angle accordingly
- Arguments
- angle - horizontal or vertical angle in degrees by which the projector is tilting relative to the normal to the projection surface.
- Return value
- Horizontal or vertical projector tilting angle accordingly
SetFOV, GetFOV
- void SetFOV(float angle) float GetFOV()
- Description
- Set or get field of View. Field of view represents projector’s beam angle. This value is necessary for correct keystone correction. The default value is 30°
- Arguments
- angle - projector’s beam angle in degrees
- Return value
- Projector’s beam angle in degrees
SetVAxisOffset, GetVAxisOffset
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void SetVAxisOffset(float v) float GetVAxisOffset()
- Description
- Set or get vertical offset of the optical axis from the normal to the projection plane. This value is required for correct keystone correction. Some projectors, particularly short throw models have their beam already at an angle to the wall. Take account of this initial angle when calculating keystone correction. The provided value is the absolute offset divided by the image height. The default value is 0
- Arguments
- v - value of vertical axis offset
- Return value
- value of vertical axis offset
SetPreRadial, GetPreRadial
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void SetPreRadial(float x, float y, float k1, float k2) void GetPreRadial(float& x, float& y, float& k1, float& k2)
- Description
- Set or get radial distortion compensation parameters. The software uses Brown-Conrady distortion model
- Arguments
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x, y – distortion center
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k1, k2 – 1st and 2nd distortion coefficients
- Return value
- None
SetCorner, GetCorner
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void SetCorner(const ECornerId& corner, float pixel_x, float pixel_y) void GetCorner(const ECornerId& corner, float& pixel_x, float& pixel_y)
- Description
- Set or get position of an individual corner point of the 4x corner warp configuration
- Arguments
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corner – corner identifier
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pixel_x, pixel_y – horizontal and vertical coordinate of the corner
- Return value
- None
SetCornerNorm, GetCornerNorm
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void SetCornerNorm(const ECornerId& corner, float x, float y) void GetCornerNorm(const ECornerId& corner, float& x, float& y)
- Description
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Set or get normalized position of an individual corner point of the 4x corner warp configuration
- Arguments
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corner – corner identifier
x,y – horizontal and vertical coordinate of the corner in the range 0..1
- Return
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None
SetArbitraryKnotsNum, GetArbitraryKnotsNum
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void SetArbitraryKnotsNum(uint32_t num) uint32_t GetArbitraryKnotsNum()
- Description
- Set or get number of control points (knots) for the arbitrary warp. Arbitrary warp is defined by a set of curves and control points arranged into NxN grid. This parameter sets the size of this grid. For simplicity the number of control points in both dimensions is the same
- Arguments
- num – number of control knots in each dimension
- Return value
- number of control knots in each dimension
SetArbitraryKnot, GetArbitraryKnot
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void SetArbitraryKnot(const uint32_t idx, const float pixel_x, const float pixel_y) void GetArbitraryKnot(const uint32_t idx, float& pixel_x, float& pixel_y)
- Description
- Set or get absolute position of individual control points. Points are numbered left to right, top to bottom
- Arguments
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idx – zero based point index number
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pixel_x, pixel_y – horizontal and vertical coordinate of the point
- Return value
- None
SetArbitraryKnotNorm, GetArbitraryKnotNorm
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void SetArbitraryKnotNorm(const uint32_t idx, const float x, const float y) void GetArbitraryKnotNorm(const uint32_t idx, float& x, float& y)
- Description
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Set or get normalized position of individual control points. Points are numbered left to right, top to bottom
- Arguments
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idx– zero based point index number
x,y – horizontal and vertical coordinate of the point in the range 0..1
- Return
- None
SetMaintainRatio, GetMaintainRatio
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void SetMaintainRatio(bool val) bool GetMaintainRatio()
- Description
- Set or get maintain aspect ratio flag. If set the aspect ratio of the input resolution is preserved. As a result the output image may have blank areas along either horizontal or vertical axis
- Arguments
- val – true to maintain input aspect ratio, false otherwise
- Return value
- Current maintain aspect ratio setting
SetShrinkToFit, GetShrinkToFit
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void SetShrinkToFit(bool val) bool GetShrinkToFit()
- Description
- Set or get shrink to fit setting. If set the resulting image is scaled down after applying all transforms to make sure it fits into the screen. Otherwise the resulting image is cropped to fit output dimensions. This flag is only relevant for the Fixed warp configuration
- Arguments
- val – true to shrink resulting image to fit output dimensions, false otherwise
- Return value
- Current shrink to fit setting
Data structures and types
ECornerId
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enum ECornerId { ETopLeft = 0, ETopRight, EBottomLeft, EBottomRight, ETotalCorners, };
- Description
- Enum identifies individual corners in the 4x corner warp configuration