--- /dev/null
+// Copyright 2011 Google Inc. All Rights Reserved.
+//
+// This code is licensed under the same terms as WebM:
+// Software License Agreement: http://www.webmproject.org/license/software/
+// Additional IP Rights Grant: http://www.webmproject.org/license/additional/
+// -----------------------------------------------------------------------------
+//
+// WebP encoder: main interface
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#ifndef WEBP_WEBP_ENCODE_H_
+#define WEBP_WEBP_ENCODE_H_
+
+#include "./types.h"
+
+#if defined(__cplusplus) || defined(c_plusplus)
+extern "C" {
+#endif
+
+#define WEBP_ENCODER_ABI_VERSION 0x0201 // MAJOR(8b) + MINOR(8b)
+
+// Note: forward declaring enumerations is not allowed in (strict) C and C++,
+// the types are left here for reference.
+// typedef enum WebPImageHint WebPImageHint;
+// typedef enum WebPEncCSP WebPEncCSP;
+// typedef enum WebPPreset WebPPreset;
+// typedef enum WebPEncodingError WebPEncodingError;
+typedef struct WebPConfig WebPConfig;
+typedef struct WebPPicture WebPPicture; // main structure for I/O
+typedef struct WebPAuxStats WebPAuxStats;
+typedef struct WebPMemoryWriter WebPMemoryWriter;
+
+// Return the encoder's version number, packed in hexadecimal using 8bits for
+// each of major/minor/revision. E.g: v2.5.7 is 0x020507.
+WEBP_EXTERN(int) WebPGetEncoderVersion(void);
+
+//------------------------------------------------------------------------------
+// One-stop-shop call! No questions asked:
+
+// Returns the size of the compressed data (pointed to by *output), or 0 if
+// an error occurred. The compressed data must be released by the caller
+// using the call 'free(*output)'.
+// These functions compress using the lossy format, and the quality_factor
+// can go from 0 (smaller output, lower quality) to 100 (best quality,
+// larger output).
+WEBP_EXTERN(size_t) WebPEncodeRGB(const uint8_t* rgb,
+ int width, int height, int stride,
+ float quality_factor, uint8_t** output);
+WEBP_EXTERN(size_t) WebPEncodeBGR(const uint8_t* bgr,
+ int width, int height, int stride,
+ float quality_factor, uint8_t** output);
+WEBP_EXTERN(size_t) WebPEncodeRGBA(const uint8_t* rgba,
+ int width, int height, int stride,
+ float quality_factor, uint8_t** output);
+WEBP_EXTERN(size_t) WebPEncodeBGRA(const uint8_t* bgra,
+ int width, int height, int stride,
+ float quality_factor, uint8_t** output);
+
+// These functions are the equivalent of the above, but compressing in a
+// lossless manner. Files are usually larger than lossy format, but will
+// not suffer any compression loss.
+WEBP_EXTERN(size_t) WebPEncodeLosslessRGB(const uint8_t* rgb,
+ int width, int height, int stride,
+ uint8_t** output);
+WEBP_EXTERN(size_t) WebPEncodeLosslessBGR(const uint8_t* bgr,
+ int width, int height, int stride,
+ uint8_t** output);
+WEBP_EXTERN(size_t) WebPEncodeLosslessRGBA(const uint8_t* rgba,
+ int width, int height, int stride,
+ uint8_t** output);
+WEBP_EXTERN(size_t) WebPEncodeLosslessBGRA(const uint8_t* bgra,
+ int width, int height, int stride,
+ uint8_t** output);
+
+//------------------------------------------------------------------------------
+// Coding parameters
+
+// Image characteristics hint for the underlying encoder.
+typedef enum WebPImageHint {
+ WEBP_HINT_DEFAULT = 0, // default preset.
+ WEBP_HINT_PICTURE, // digital picture, like portrait, inner shot
+ WEBP_HINT_PHOTO, // outdoor photograph, with natural lighting
+ WEBP_HINT_GRAPH, // Discrete tone image (graph, map-tile etc).
+ WEBP_HINT_LAST
+} WebPImageHint;
+
+// Compression parameters.
+struct WebPConfig {
+ int lossless; // Lossless encoding (0=lossy(default), 1=lossless).
+ float quality; // between 0 (smallest file) and 100 (biggest)
+ int method; // quality/speed trade-off (0=fast, 6=slower-better)
+
+ WebPImageHint image_hint; // Hint for image type (lossless only for now).
+
+ // Parameters related to lossy compression only:
+ int target_size; // if non-zero, set the desired target size in bytes.
+ // Takes precedence over the 'compression' parameter.
+ float target_PSNR; // if non-zero, specifies the minimal distortion to
+ // try to achieve. Takes precedence over target_size.
+ int segments; // maximum number of segments to use, in [1..4]
+ int sns_strength; // Spatial Noise Shaping. 0=off, 100=maximum.
+ int filter_strength; // range: [0 = off .. 100 = strongest]
+ int filter_sharpness; // range: [0 = off .. 7 = least sharp]
+ int filter_type; // filtering type: 0 = simple, 1 = strong (only used
+ // if filter_strength > 0 or autofilter > 0)
+ int autofilter; // Auto adjust filter's strength [0 = off, 1 = on]
+ int alpha_compression; // Algorithm for encoding the alpha plane (0 = none,
+ // 1 = compressed with WebP lossless). Default is 1.
+ int alpha_filtering; // Predictive filtering method for alpha plane.
+ // 0: none, 1: fast, 2: best. Default if 1.
+ int alpha_quality; // Between 0 (smallest size) and 100 (lossless).
+ // Default is 100.
+ int pass; // number of entropy-analysis passes (in [1..10]).
+
+ int show_compressed; // if true, export the compressed picture back.
+ // In-loop filtering is not applied.
+ int preprocessing; // preprocessing filter (0=none, 1=segment-smooth)
+ int partitions; // log2(number of token partitions) in [0..3]. Default
+ // is set to 0 for easier progressive decoding.
+ int partition_limit; // quality degradation allowed to fit the 512k limit
+ // on prediction modes coding (0: no degradation,
+ // 100: maximum possible degradation).
+ int emulate_jpeg_size; // If true, compression parameters will be remapped
+ // to better match the expected output size from
+ // JPEG compression. Generally, the output size will
+ // be similar but the degradation will be lower.
+ int thread_level; // If non-zero, try and use multi-threaded encoding.
+ int low_memory; // If set, reduce memory usage (but increase CPU use).
+
+ uint32_t pad[5]; // padding for later use
+};
+
+// Enumerate some predefined settings for WebPConfig, depending on the type
+// of source picture. These presets are used when calling WebPConfigPreset().
+typedef enum WebPPreset {
+ WEBP_PRESET_DEFAULT = 0, // default preset.
+ WEBP_PRESET_PICTURE, // digital picture, like portrait, inner shot
+ WEBP_PRESET_PHOTO, // outdoor photograph, with natural lighting
+ WEBP_PRESET_DRAWING, // hand or line drawing, with high-contrast details
+ WEBP_PRESET_ICON, // small-sized colorful images
+ WEBP_PRESET_TEXT // text-like
+} WebPPreset;
+
+// Internal, version-checked, entry point
+WEBP_EXTERN(int) WebPConfigInitInternal(WebPConfig*, WebPPreset, float, int);
+
+// Should always be called, to initialize a fresh WebPConfig structure before
+// modification. Returns false in case of version mismatch. WebPConfigInit()
+// must have succeeded before using the 'config' object.
+// Note that the default values are lossless=0 and quality=75.
+static WEBP_INLINE int WebPConfigInit(WebPConfig* config) {
+ return WebPConfigInitInternal(config, WEBP_PRESET_DEFAULT, 75.f,
+ WEBP_ENCODER_ABI_VERSION);
+}
+
+// This function will initialize the configuration according to a predefined
+// set of parameters (referred to by 'preset') and a given quality factor.
+// This function can be called as a replacement to WebPConfigInit(). Will
+// return false in case of error.
+static WEBP_INLINE int WebPConfigPreset(WebPConfig* config,
+ WebPPreset preset, float quality) {
+ return WebPConfigInitInternal(config, preset, quality,
+ WEBP_ENCODER_ABI_VERSION);
+}
+
+// Returns true if 'config' is non-NULL and all configuration parameters are
+// within their valid ranges.
+WEBP_EXTERN(int) WebPValidateConfig(const WebPConfig* config);
+
+//------------------------------------------------------------------------------
+// Input / Output
+// Structure for storing auxiliary statistics (mostly for lossy encoding).
+
+struct WebPAuxStats {
+ int coded_size; // final size
+
+ float PSNR[5]; // peak-signal-to-noise ratio for Y/U/V/All/Alpha
+ int block_count[3]; // number of intra4/intra16/skipped macroblocks
+ int header_bytes[2]; // approximate number of bytes spent for header
+ // and mode-partition #0
+ int residual_bytes[3][4]; // approximate number of bytes spent for
+ // DC/AC/uv coefficients for each (0..3) segments.
+ int segment_size[4]; // number of macroblocks in each segments
+ int segment_quant[4]; // quantizer values for each segments
+ int segment_level[4]; // filtering strength for each segments [0..63]
+
+ int alpha_data_size; // size of the transparency data
+ int layer_data_size; // size of the enhancement layer data
+
+ // lossless encoder statistics
+ uint32_t lossless_features; // bit0:predictor bit1:cross-color transform
+ // bit2:subtract-green bit3:color indexing
+ int histogram_bits; // number of precision bits of histogram
+ int transform_bits; // precision bits for transform
+ int cache_bits; // number of bits for color cache lookup
+ int palette_size; // number of color in palette, if used
+ int lossless_size; // final lossless size
+
+ uint32_t pad[4]; // padding for later use
+};
+
+// Signature for output function. Should return true if writing was successful.
+// data/data_size is the segment of data to write, and 'picture' is for
+// reference (and so one can make use of picture->custom_ptr).
+typedef int (*WebPWriterFunction)(const uint8_t* data, size_t data_size,
+ const WebPPicture* picture);
+
+// WebPMemoryWrite: a special WebPWriterFunction that writes to memory using
+// the following WebPMemoryWriter object (to be set as a custom_ptr).
+struct WebPMemoryWriter {
+ uint8_t* mem; // final buffer (of size 'max_size', larger than 'size').
+ size_t size; // final size
+ size_t max_size; // total capacity
+ uint32_t pad[1]; // padding for later use
+};
+
+// The following must be called first before any use.
+WEBP_EXTERN(void) WebPMemoryWriterInit(WebPMemoryWriter* writer);
+
+// The custom writer to be used with WebPMemoryWriter as custom_ptr. Upon
+// completion, writer.mem and writer.size will hold the coded data.
+// writer.mem must be freed using the call 'free(writer.mem)'.
+WEBP_EXTERN(int) WebPMemoryWrite(const uint8_t* data, size_t data_size,
+ const WebPPicture* picture);
+
+// Progress hook, called from time to time to report progress. It can return
+// false to request an abort of the encoding process, or true otherwise if
+// everything is OK.
+typedef int (*WebPProgressHook)(int percent, const WebPPicture* picture);
+
+// Color spaces.
+typedef enum WebPEncCSP {
+ // chroma sampling
+ WEBP_YUV420 = 0, // 4:2:0
+ WEBP_YUV422 = 1, // 4:2:2
+ WEBP_YUV444 = 2, // 4:4:4
+ WEBP_YUV400 = 3, // grayscale
+ WEBP_CSP_UV_MASK = 3, // bit-mask to get the UV sampling factors
+ // alpha channel variants
+ WEBP_YUV420A = 4,
+ WEBP_YUV422A = 5,
+ WEBP_YUV444A = 6,
+ WEBP_YUV400A = 7, // grayscale + alpha
+ WEBP_CSP_ALPHA_BIT = 4 // bit that is set if alpha is present
+} WebPEncCSP;
+
+// Encoding error conditions.
+typedef enum WebPEncodingError {
+ VP8_ENC_OK = 0,
+ VP8_ENC_ERROR_OUT_OF_MEMORY, // memory error allocating objects
+ VP8_ENC_ERROR_BITSTREAM_OUT_OF_MEMORY, // memory error while flushing bits
+ VP8_ENC_ERROR_NULL_PARAMETER, // a pointer parameter is NULL
+ VP8_ENC_ERROR_INVALID_CONFIGURATION, // configuration is invalid
+ VP8_ENC_ERROR_BAD_DIMENSION, // picture has invalid width/height
+ VP8_ENC_ERROR_PARTITION0_OVERFLOW, // partition is bigger than 512k
+ VP8_ENC_ERROR_PARTITION_OVERFLOW, // partition is bigger than 16M
+ VP8_ENC_ERROR_BAD_WRITE, // error while flushing bytes
+ VP8_ENC_ERROR_FILE_TOO_BIG, // file is bigger than 4G
+ VP8_ENC_ERROR_USER_ABORT, // abort request by user
+ VP8_ENC_ERROR_LAST // list terminator. always last.
+} WebPEncodingError;
+
+// maximum width/height allowed (inclusive), in pixels
+#define WEBP_MAX_DIMENSION 16383
+
+// Main exchange structure (input samples, output bytes, statistics)
+struct WebPPicture {
+ // INPUT
+ //////////////
+ // Main flag for encoder selecting between ARGB or YUV input.
+ // It is recommended to use ARGB input (*argb, argb_stride) for lossless
+ // compression, and YUV input (*y, *u, *v, etc.) for lossy compression
+ // since these are the respective native colorspace for these formats.
+ int use_argb;
+
+ // YUV input (mostly used for input to lossy compression)
+ WebPEncCSP colorspace; // colorspace: should be YUV420 for now (=Y'CbCr).
+ int width, height; // dimensions (less or equal to WEBP_MAX_DIMENSION)
+ uint8_t *y, *u, *v; // pointers to luma/chroma planes.
+ int y_stride, uv_stride; // luma/chroma strides.
+ uint8_t* a; // pointer to the alpha plane
+ int a_stride; // stride of the alpha plane
+ uint32_t pad1[2]; // padding for later use
+
+ // ARGB input (mostly used for input to lossless compression)
+ uint32_t* argb; // Pointer to argb (32 bit) plane.
+ int argb_stride; // This is stride in pixels units, not bytes.
+ uint32_t pad2[3]; // padding for later use
+
+ // OUTPUT
+ ///////////////
+ // Byte-emission hook, to store compressed bytes as they are ready.
+ WebPWriterFunction writer; // can be NULL
+ void* custom_ptr; // can be used by the writer.
+
+ // map for extra information (only for lossy compression mode)
+ int extra_info_type; // 1: intra type, 2: segment, 3: quant
+ // 4: intra-16 prediction mode,
+ // 5: chroma prediction mode,
+ // 6: bit cost, 7: distortion
+ uint8_t* extra_info; // if not NULL, points to an array of size
+ // ((width + 15) / 16) * ((height + 15) / 16) that
+ // will be filled with a macroblock map, depending
+ // on extra_info_type.
+
+ // STATS AND REPORTS
+ ///////////////////////////
+ // Pointer to side statistics (updated only if not NULL)
+ WebPAuxStats* stats;
+
+ // Error code for the latest error encountered during encoding
+ WebPEncodingError error_code;
+
+ // If not NULL, report progress during encoding.
+ WebPProgressHook progress_hook;
+
+ void* user_data; // this field is free to be set to any value and
+ // used during callbacks (like progress-report e.g.).
+
+ uint32_t pad3[3]; // padding for later use
+
+ // Unused for now: original samples (for non-YUV420 modes)
+ uint8_t *u0, *v0;
+ int uv0_stride;
+
+ uint32_t pad4[7]; // padding for later use
+
+ // PRIVATE FIELDS
+ ////////////////////
+ void* memory_; // row chunk of memory for yuva planes
+ void* memory_argb_; // and for argb too.
+ void* pad5[2]; // padding for later use
+};
+
+// Internal, version-checked, entry point
+WEBP_EXTERN(int) WebPPictureInitInternal(WebPPicture*, int);
+
+// Should always be called, to initialize the structure. Returns false in case
+// of version mismatch. WebPPictureInit() must have succeeded before using the
+// 'picture' object.
+// Note that, by default, use_argb is false and colorspace is WEBP_YUV420.
+static WEBP_INLINE int WebPPictureInit(WebPPicture* picture) {
+ return WebPPictureInitInternal(picture, WEBP_ENCODER_ABI_VERSION);
+}
+
+//------------------------------------------------------------------------------
+// WebPPicture utils
+
+// Convenience allocation / deallocation based on picture->width/height:
+// Allocate y/u/v buffers as per colorspace/width/height specification.
+// Note! This function will free the previous buffer if needed.
+// Returns false in case of memory error.
+WEBP_EXTERN(int) WebPPictureAlloc(WebPPicture* picture);
+
+// Release the memory allocated by WebPPictureAlloc() or WebPPictureImport*().
+// Note that this function does _not_ free the memory used by the 'picture'
+// object itself.
+// Besides memory (which is reclaimed) all other fields of 'picture' are
+// preserved.
+WEBP_EXTERN(void) WebPPictureFree(WebPPicture* picture);
+
+// Copy the pixels of *src into *dst, using WebPPictureAlloc. Upon return,
+// *dst will fully own the copied pixels (this is not a view).
+// Returns false in case of memory allocation error.
+WEBP_EXTERN(int) WebPPictureCopy(const WebPPicture* src, WebPPicture* dst);
+
+// Compute PSNR, SSIM or LSIM distortion metric between two pictures.
+// Result is in dB, stores in result[] in the Y/U/V/Alpha/All order.
+// Returns false in case of error (src and ref don't have same dimension, ...)
+// Warning: this function is rather CPU-intensive.
+WEBP_EXTERN(int) WebPPictureDistortion(
+ const WebPPicture* src, const WebPPicture* ref,
+ int metric_type, // 0 = PSNR, 1 = SSIM, 2 = LSIM
+ float result[5]);
+
+// self-crops a picture to the rectangle defined by top/left/width/height.
+// Returns false in case of memory allocation error, or if the rectangle is
+// outside of the source picture.
+// The rectangle for the view is defined by the top-left corner pixel
+// coordinates (left, top) as well as its width and height. This rectangle
+// must be fully be comprised inside the 'src' source picture. If the source
+// picture uses the YUV420 colorspace, the top and left coordinates will be
+// snapped to even values.
+WEBP_EXTERN(int) WebPPictureCrop(WebPPicture* picture,
+ int left, int top, int width, int height);
+
+// Extracts a view from 'src' picture into 'dst'. The rectangle for the view
+// is defined by the top-left corner pixel coordinates (left, top) as well
+// as its width and height. This rectangle must be fully be comprised inside
+// the 'src' source picture. If the source picture uses the YUV420 colorspace,
+// the top and left coordinates will be snapped to even values.
+// Picture 'src' must out-live 'dst' picture. Self-extraction of view is allowed
+// ('src' equal to 'dst') as a mean of fast-cropping (but note that doing so,
+// the original dimension will be lost).
+// Returns false in case of memory allocation error or invalid parameters.
+WEBP_EXTERN(int) WebPPictureView(const WebPPicture* src,
+ int left, int top, int width, int height,
+ WebPPicture* dst);
+
+// Returns true if the 'picture' is actually a view and therefore does
+// not own the memory for pixels.
+WEBP_EXTERN(int) WebPPictureIsView(const WebPPicture* picture);
+
+// Rescale a picture to new dimension width x height.
+// Now gamma correction is applied.
+// Returns false in case of error (invalid parameter or insufficient memory).
+WEBP_EXTERN(int) WebPPictureRescale(WebPPicture* pic, int width, int height);
+
+// Colorspace conversion function to import RGB samples.
+// Previous buffer will be free'd, if any.
+// *rgb buffer should have a size of at least height * rgb_stride.
+// Returns false in case of memory error.
+WEBP_EXTERN(int) WebPPictureImportRGB(
+ WebPPicture* picture, const uint8_t* rgb, int rgb_stride);
+// Same, but for RGBA buffer.
+WEBP_EXTERN(int) WebPPictureImportRGBA(
+ WebPPicture* picture, const uint8_t* rgba, int rgba_stride);
+// Same, but for RGBA buffer. Imports the RGB direct from the 32-bit format
+// input buffer ignoring the alpha channel. Avoids needing to copy the data
+// to a temporary 24-bit RGB buffer to import the RGB only.
+WEBP_EXTERN(int) WebPPictureImportRGBX(
+ WebPPicture* picture, const uint8_t* rgbx, int rgbx_stride);
+
+// Variants of the above, but taking BGR(A|X) input.
+WEBP_EXTERN(int) WebPPictureImportBGR(
+ WebPPicture* picture, const uint8_t* bgr, int bgr_stride);
+WEBP_EXTERN(int) WebPPictureImportBGRA(
+ WebPPicture* picture, const uint8_t* bgra, int bgra_stride);
+WEBP_EXTERN(int) WebPPictureImportBGRX(
+ WebPPicture* picture, const uint8_t* bgrx, int bgrx_stride);
+
+// Converts picture->argb data to the YUVA format specified by 'colorspace'.
+// Upon return, picture->use_argb is set to false. The presence of real
+// non-opaque transparent values is detected, and 'colorspace' will be
+// adjusted accordingly. Note that this method is lossy.
+// Returns false in case of error.
+WEBP_EXTERN(int) WebPPictureARGBToYUVA(WebPPicture* picture,
+ WebPEncCSP colorspace);
+
+// Converts picture->yuv to picture->argb and sets picture->use_argb to true.
+// The input format must be YUV_420 or YUV_420A.
+// Note that the use of this method is discouraged if one has access to the
+// raw ARGB samples, since using YUV420 is comparatively lossy. Also, the
+// conversion from YUV420 to ARGB incurs a small loss too.
+// Returns false in case of error.
+WEBP_EXTERN(int) WebPPictureYUVAToARGB(WebPPicture* picture);
+
+// Helper function: given a width x height plane of YUV(A) samples
+// (with stride 'stride'), clean-up the YUV samples under fully transparent
+// area, to help compressibility (no guarantee, though).
+WEBP_EXTERN(void) WebPCleanupTransparentArea(WebPPicture* picture);
+
+// Scan the picture 'picture' for the presence of non fully opaque alpha values.
+// Returns true in such case. Otherwise returns false (indicating that the
+// alpha plane can be ignored altogether e.g.).
+WEBP_EXTERN(int) WebPPictureHasTransparency(const WebPPicture* picture);
+
+// Remove the transparency information (if present) by blending the color with
+// the background color 'background_rgb' (specified as 24bit RGB triplet).
+// After this call, all alpha values are reset to 0xff.
+WEBP_EXTERN(void) WebPBlendAlpha(WebPPicture* pic, uint32_t background_rgb);
+
+//------------------------------------------------------------------------------
+// Main call
+
+// Main encoding call, after config and picture have been initialized.
+// 'picture' must be less than 16384x16384 in dimension (cf WEBP_MAX_DIMENSION),
+// and the 'config' object must be a valid one.
+// Returns false in case of error, true otherwise.
+// In case of error, picture->error_code is updated accordingly.
+// 'picture' can hold the source samples in both YUV(A) or ARGB input, depending
+// on the value of 'picture->use_argb'. It is highly recommended to use
+// the former for lossy encoding, and the latter for lossless encoding
+// (when config.lossless is true). Automatic conversion from one format to
+// another is provided but they both incur some loss.
+WEBP_EXTERN(int) WebPEncode(const WebPConfig* config, WebPPicture* picture);
+
+//------------------------------------------------------------------------------
+
+#if defined(__cplusplus) || defined(c_plusplus)
+} // extern "C"
+#endif
+
+#endif /* WEBP_WEBP_ENCODE_H_ */
git.r.bdr.sh / rbdr / super-polarity / blobdiff