robocar-tools/vendor/gocv.io/x/gocv/imgcodecs.go

253 lines
8.5 KiB
Go

package gocv
/*
#include <stdlib.h>
#include "imgcodecs.h"
*/
import "C"
import (
"unsafe"
)
// IMReadFlag is one of the valid flags to use for the IMRead function.
type IMReadFlag int
const (
// IMReadUnchanged return the loaded image as is (with alpha channel,
// otherwise it gets cropped).
IMReadUnchanged IMReadFlag = -1
// IMReadGrayScale always convert image to the single channel
// grayscale image.
IMReadGrayScale IMReadFlag = 0
// IMReadColor always converts image to the 3 channel BGR color image.
IMReadColor IMReadFlag = 1
// IMReadAnyDepth returns 16-bit/32-bit image when the input has the corresponding
// depth, otherwise convert it to 8-bit.
IMReadAnyDepth IMReadFlag = 2
// IMReadAnyColor the image is read in any possible color format.
IMReadAnyColor IMReadFlag = 4
// IMReadLoadGDAL uses the gdal driver for loading the image.
IMReadLoadGDAL IMReadFlag = 8
// IMReadReducedGrayscale2 always converts image to the single channel grayscale image
// and the image size reduced 1/2.
IMReadReducedGrayscale2 IMReadFlag = 16
// IMReadReducedColor2 always converts image to the 3 channel BGR color image and the
// image size reduced 1/2.
IMReadReducedColor2 IMReadFlag = 17
// IMReadReducedGrayscale4 always converts image to the single channel grayscale image and
// the image size reduced 1/4.
IMReadReducedGrayscale4 IMReadFlag = 32
// IMReadReducedColor4 always converts image to the 3 channel BGR color image and
// the image size reduced 1/4.
IMReadReducedColor4 IMReadFlag = 33
// IMReadReducedGrayscale8 always convert image to the single channel grayscale image and
// the image size reduced 1/8.
IMReadReducedGrayscale8 IMReadFlag = 64
// IMReadReducedColor8 always convert image to the 3 channel BGR color image and the
// image size reduced 1/8.
IMReadReducedColor8 IMReadFlag = 65
// IMReadIgnoreOrientation do not rotate the image according to EXIF's orientation flag.
IMReadIgnoreOrientation IMReadFlag = 128
)
// TODO: Define IMWriteFlag type?
const (
//IMWriteJpegQuality is the quality from 0 to 100 for JPEG (the higher is the better). Default value is 95.
IMWriteJpegQuality = 1
// IMWriteJpegProgressive enables JPEG progressive feature, 0 or 1, default is False.
IMWriteJpegProgressive = 2
// IMWriteJpegOptimize enables JPEG optimization, 0 or 1, default is False.
IMWriteJpegOptimize = 3
// IMWriteJpegRstInterval is the JPEG restart interval, 0 - 65535, default is 0 - no restart.
IMWriteJpegRstInterval = 4
// IMWriteJpegLumaQuality separates luma quality level, 0 - 100, default is 0 - don't use.
IMWriteJpegLumaQuality = 5
// IMWriteJpegChromaQuality separates chroma quality level, 0 - 100, default is 0 - don't use.
IMWriteJpegChromaQuality = 6
// IMWritePngCompression is the compression level from 0 to 9 for PNG. A
// higher value means a smaller size and longer compression time.
// If specified, strategy is changed to IMWRITE_PNG_STRATEGY_DEFAULT (Z_DEFAULT_STRATEGY).
// Default value is 1 (best speed setting).
IMWritePngCompression = 16
// IMWritePngStrategy is one of cv::IMWritePNGFlags, default is IMWRITE_PNG_STRATEGY_RLE.
IMWritePngStrategy = 17
// IMWritePngBilevel is the binary level PNG, 0 or 1, default is 0.
IMWritePngBilevel = 18
// IMWritePxmBinary for PPM, PGM, or PBM can be a binary format flag, 0 or 1. Default value is 1.
IMWritePxmBinary = 32
// IMWriteWebpQuality is the quality from 1 to 100 for WEBP (the higher is
// the better). By default (without any parameter) and for quality above
// 100 the lossless compression is used.
IMWriteWebpQuality = 64
// IMWritePamTupletype sets the TUPLETYPE field to the corresponding string
// value that is defined for the format.
IMWritePamTupletype = 128
// IMWritePngStrategyDefault is the value to use for normal data.
IMWritePngStrategyDefault = 0
// IMWritePngStrategyFiltered is the value to use for data produced by a
// filter (or predictor). Filtered data consists mostly of small values
// with a somewhat random distribution. In this case, the compression
// algorithm is tuned to compress them better.
IMWritePngStrategyFiltered = 1
// IMWritePngStrategyHuffmanOnly forces Huffman encoding only (no string match).
IMWritePngStrategyHuffmanOnly = 2
// IMWritePngStrategyRle is the value to use to limit match distances to
// one (run-length encoding).
IMWritePngStrategyRle = 3
// IMWritePngStrategyFixed is the value to prevent the use of dynamic
// Huffman codes, allowing for a simpler decoder for special applications.
IMWritePngStrategyFixed = 4
)
// IMRead reads an image from a file into a Mat.
// The flags param is one of the IMReadFlag flags.
// If the image cannot be read (because of missing file, improper permissions,
// unsupported or invalid format), the function returns an empty Mat.
//
// For further details, please see:
// http://docs.opencv.org/master/d4/da8/group__imgcodecs.html#ga288b8b3da0892bd651fce07b3bbd3a56
//
func IMRead(name string, flags IMReadFlag) Mat {
cName := C.CString(name)
defer C.free(unsafe.Pointer(cName))
return newMat(C.Image_IMRead(cName, C.int(flags)))
}
// IMWrite writes a Mat to an image file.
//
// For further details, please see:
// http://docs.opencv.org/master/d4/da8/group__imgcodecs.html#gabbc7ef1aa2edfaa87772f1202d67e0ce
//
func IMWrite(name string, img Mat) bool {
cName := C.CString(name)
defer C.free(unsafe.Pointer(cName))
return bool(C.Image_IMWrite(cName, img.p))
}
// IMWriteWithParams writes a Mat to an image file. With that func you can
// pass compression parameters.
//
// For further details, please see:
// http://docs.opencv.org/master/d4/da8/group__imgcodecs.html#gabbc7ef1aa2edfaa87772f1202d67e0ce
//
func IMWriteWithParams(name string, img Mat, params []int) bool {
cName := C.CString(name)
defer C.free(unsafe.Pointer(cName))
cparams := []C.int{}
for _, v := range params {
cparams = append(cparams, C.int(v))
}
paramsVector := C.struct_IntVector{}
paramsVector.val = (*C.int)(&cparams[0])
paramsVector.length = (C.int)(len(cparams))
return bool(C.Image_IMWrite_WithParams(cName, img.p, paramsVector))
}
// FileExt represents a file extension.
type FileExt string
const (
// PNGFileExt is the file extension for PNG.
PNGFileExt FileExt = ".png"
// JPEGFileExt is the file extension for JPEG.
JPEGFileExt FileExt = ".jpg"
// GIFFileExt is the file extension for GIF.
GIFFileExt FileExt = ".gif"
)
// IMEncode encodes an image Mat into a memory buffer.
// This function compresses the image and stores it in the returned memory buffer,
// using the image format passed in in the form of a file extension string.
//
// For further details, please see:
// http://docs.opencv.org/master/d4/da8/group__imgcodecs.html#ga461f9ac09887e47797a54567df3b8b63
//
func IMEncode(fileExt FileExt, img Mat) (buf *NativeByteBuffer, err error) {
cfileExt := C.CString(string(fileExt))
defer C.free(unsafe.Pointer(cfileExt))
buffer := newNativeByteBuffer()
C.Image_IMEncode(cfileExt, img.Ptr(), buffer.nativePointer())
return buffer, nil
}
// IMEncodeWithParams encodes an image Mat into a memory buffer.
// This function compresses the image and stores it in the returned memory buffer,
// using the image format passed in in the form of a file extension string.
//
// Usage example:
// buffer, err := gocv.IMEncodeWithParams(gocv.JPEGFileExt, img, []int{gocv.IMWriteJpegQuality, quality})
//
// For further details, please see:
// http://docs.opencv.org/master/d4/da8/group__imgcodecs.html#ga461f9ac09887e47797a54567df3b8b63
//
func IMEncodeWithParams(fileExt FileExt, img Mat, params []int) (buf *NativeByteBuffer, err error) {
cfileExt := C.CString(string(fileExt))
defer C.free(unsafe.Pointer(cfileExt))
cparams := []C.int{}
for _, v := range params {
cparams = append(cparams, C.int(v))
}
paramsVector := C.struct_IntVector{}
paramsVector.val = (*C.int)(&cparams[0])
paramsVector.length = (C.int)(len(cparams))
b := newNativeByteBuffer()
C.Image_IMEncode_WithParams(cfileExt, img.Ptr(), paramsVector, b.nativePointer())
return b, nil
}
// IMDecode reads an image from a buffer in memory.
// The function IMDecode reads an image from the specified buffer in memory.
// If the buffer is too short or contains invalid data, the function
// returns an empty matrix.
//
// For further details, please see:
// https://docs.opencv.org/master/d4/da8/group__imgcodecs.html#ga26a67788faa58ade337f8d28ba0eb19e
//
func IMDecode(buf []byte, flags IMReadFlag) (Mat, error) {
data, err := toByteArray(buf)
if err != nil {
return Mat{}, err
}
return newMat(C.Image_IMDecode(*data, C.int(flags))), nil
}