diff options
Diffstat (limited to 'include/webp/decode.h')
| -rw-r--r-- | include/webp/decode.h | 104 |
1 files changed, 39 insertions, 65 deletions
diff --git a/include/webp/decode.h b/include/webp/decode.h index d82daa0a..43b6c58f 100644 --- a/include/webp/decode.h +++ b/include/webp/decode.h @@ -20,18 +20,6 @@ extern "C" { #define WEBP_DECODER_ABI_VERSION 0x0200 // MAJOR(8b) + MINOR(8b) -typedef struct WebPRGBABuffer WebPRGBABuffer; -typedef struct WebPYUVABuffer WebPYUVABuffer; -typedef struct WebPDecBuffer WebPDecBuffer; -#if !(defined(__cplusplus) || defined(c_plusplus)) -typedef enum VP8StatusCode VP8StatusCode; -typedef enum WEBP_CSP_MODE WEBP_CSP_MODE; -#endif -typedef struct WebPIDecoder WebPIDecoder; -typedef struct WebPBitstreamFeatures WebPBitstreamFeatures; -typedef struct WebPDecoderOptions WebPDecoderOptions; -typedef struct WebPDecoderConfig WebPDecoderConfig; - // Return the decoder's version number, packed in hexadecimal using 8bits for // each of major/minor/revision. E.g: v2.5.7 is 0x020507. WEBP_EXTERN(int) WebPGetDecoderVersion(void); @@ -130,28 +118,20 @@ WEBP_EXTERN(uint8_t*) WebPDecodeYUVInto( // Note: the naming describes the byte-ordering of packed samples in memory. // For instance, MODE_BGRA relates to samples ordered as B,G,R,A,B,G,R,A,... // Non-capital names (e.g.:MODE_Argb) relates to pre-multiplied RGB channels. -// RGBA-4444 and RGB-565 colorspaces are represented by following byte-order: -// RGBA-4444: [r3 r2 r1 r0 g3 g2 g1 g0], [b3 b2 b1 b0 a3 a2 a1 a0], ... -// RGB-565: [r4 r3 r2 r1 r0 g5 g4 g3], [g2 g1 g0 b4 b3 b2 b1 b0], ... -// In the case WEBP_SWAP_16BITS_CSP is defined, the bytes are swapped for -// these two modes: -// RGBA-4444: [b3 b2 b1 b0 a3 a2 a1 a0], [r3 r2 r1 r0 g3 g2 g1 g0], ... -// RGB-565: [g2 g1 g0 b4 b3 b2 b1 b0], [r4 r3 r2 r1 r0 g5 g4 g3], ... - -enum WEBP_CSP_MODE { - MODE_RGB = 0, MODE_RGBA = 1, - MODE_BGR = 2, MODE_BGRA = 3, - MODE_ARGB = 4, MODE_RGBA_4444 = 5, - MODE_RGB_565 = 6, - // RGB-premultiplied transparent modes (alpha value is preserved) - MODE_rgbA = 7, - MODE_bgrA = 8, - MODE_Argb = 9, - MODE_rgbA_4444 = 10, - // YUV modes must come after RGB ones. - MODE_YUV = 11, MODE_YUVA = 12, // yuv 4:2:0 - MODE_LAST = 13 -}; +// RGB-565 and RGBA-4444 are also endian-agnostic and byte-oriented. +typedef enum { MODE_RGB = 0, MODE_RGBA = 1, + MODE_BGR = 2, MODE_BGRA = 3, + MODE_ARGB = 4, MODE_RGBA_4444 = 5, + MODE_RGB_565 = 6, + // RGB-premultiplied transparent modes (alpha value is preserved) + MODE_rgbA = 7, + MODE_bgrA = 8, + MODE_Argb = 9, + MODE_rgbA_4444 = 10, + // YUV modes must come after RGB ones. + MODE_YUV = 11, MODE_YUVA = 12, // yuv 4:2:0 + MODE_LAST = 13 + } WEBP_CSP_MODE; // Some useful macros: static WEBP_INLINE int WebPIsPremultipliedMode(WEBP_CSP_MODE mode) { @@ -172,13 +152,13 @@ static WEBP_INLINE int WebPIsRGBMode(WEBP_CSP_MODE mode) { //------------------------------------------------------------------------------ // WebPDecBuffer: Generic structure for describing the output sample buffer. -struct WebPRGBABuffer { // view as RGBA +typedef struct { // view as RGBA uint8_t* rgba; // pointer to RGBA samples int stride; // stride in bytes from one scanline to the next. size_t size; // total size of the *rgba buffer. -}; +} WebPRGBABuffer; -struct WebPYUVABuffer { // view as YUVA +typedef struct { // view as YUVA uint8_t* y, *u, *v, *a; // pointer to luma, chroma U/V, alpha samples int y_stride; // luma stride int u_stride, v_stride; // chroma strides @@ -186,10 +166,10 @@ struct WebPYUVABuffer { // view as YUVA size_t y_size; // luma plane size size_t u_size, v_size; // chroma planes size size_t a_size; // alpha-plane size -}; +} WebPYUVABuffer; // Output buffer -struct WebPDecBuffer { +typedef struct { WEBP_CSP_MODE colorspace; // Colorspace. int width, height; // Dimensions. int is_external_memory; // If true, 'internal_memory' pointer is not used. @@ -202,7 +182,7 @@ struct WebPDecBuffer { uint8_t* private_memory; // Internally allocated memory (only when // is_external_memory is false). Should not be used // externally, but accessed via the buffer union. -}; +} WebPDecBuffer; // Internal, version-checked, entry point WEBP_EXTERN(int) WebPInitDecBufferInternal(WebPDecBuffer*, int); @@ -220,7 +200,7 @@ WEBP_EXTERN(void) WebPFreeDecBuffer(WebPDecBuffer* buffer); //------------------------------------------------------------------------------ // Enumeration of the status codes -enum VP8StatusCode { +typedef enum { VP8_STATUS_OK = 0, VP8_STATUS_OUT_OF_MEMORY, VP8_STATUS_INVALID_PARAM, @@ -229,7 +209,7 @@ enum VP8StatusCode { VP8_STATUS_SUSPENDED, VP8_STATUS_USER_ABORT, VP8_STATUS_NOT_ENOUGH_DATA -}; +} VP8StatusCode; //------------------------------------------------------------------------------ // Incremental decoding @@ -257,6 +237,8 @@ enum VP8StatusCode { // } // WebPIDelete(idec); +typedef struct WebPIDecoder WebPIDecoder; + // Creates a new incremental decoder with the supplied buffer parameter. // This output_buffer can be passed NULL, in which case a default output buffer // is used (with MODE_RGB). Otherwise, an internal reference to 'output_buffer' @@ -269,27 +251,19 @@ WEBP_EXTERN(WebPIDecoder*) WebPINewDecoder(WebPDecBuffer* output_buffer); // will output the RGB/A samples specified by 'csp' into a preallocated // buffer 'output_buffer'. The size of this buffer is at least // 'output_buffer_size' and the stride (distance in bytes between two scanlines) -// is specified by 'output_stride'. -// Additionally, output_buffer can be passed NULL in which case the output -// buffer will be allocated automatically when the decoding starts. The -// colorspace 'csp' is taken into account for allocating this buffer. All other -// parameters are ignored. -// Returns NULL if the allocation failed, or if some parameters are invalid. +// is specified by 'output_stride'. Returns NULL if the allocation failed. WEBP_EXTERN(WebPIDecoder*) WebPINewRGB( WEBP_CSP_MODE csp, uint8_t* output_buffer, size_t output_buffer_size, int output_stride); // This function allocates and initializes an incremental-decoder object, which -// will output the raw luma/chroma samples into a preallocated planes if -// supplied. The luma plane is specified by its pointer 'luma', its size -// 'luma_size' and its stride 'luma_stride'. Similarly, the chroma-u plane -// is specified by the 'u', 'u_size' and 'u_stride' parameters, and the chroma-v -// plane by 'v' and 'v_size'. And same for the alpha-plane. The 'a' pointer -// can be pass NULL in case one is not interested in the transparency plane. -// Conversely, 'luma' can be passed NULL if no preallocated planes are supplied. -// In this case, the output buffer will be automatically allocated (using -// MODE_YUVA) when decoding starts. All parameters are then ignored. -// Returns NULL if the allocation failed or if a parameter is invalid. +// will output the raw luma/chroma samples into a preallocated planes. The luma +// plane is specified by its pointer 'luma', its size 'luma_size' and its stride +// 'luma_stride'. Similarly, the chroma-u plane is specified by the 'u', +// 'u_size' and 'u_stride' parameters, and the chroma-v plane by 'v' +// and 'v_size'. And same for the alpha-plane. The 'a' pointer can be pass +// NULL in case one is not interested in the transparency plane. +// Returns NULL if the allocation failed. WEBP_EXTERN(WebPIDecoder*) WebPINewYUVA( uint8_t* luma, size_t luma_size, int luma_stride, uint8_t* u, size_t u_size, int u_stride, @@ -370,7 +344,7 @@ WEBP_EXTERN(const WebPDecBuffer*) WebPIDecodedArea( CHECK(WebPGetFeatures(data, data_size, &config.input) == VP8_STATUS_OK); // C) Adjust 'config', if needed - config.no_fancy_upsampling = 1; + config.no_fancy = 1; config.output.colorspace = MODE_BGRA; // etc. @@ -391,7 +365,7 @@ WEBP_EXTERN(const WebPDecBuffer*) WebPIDecodedArea( */ // Features gathered from the bitstream -struct WebPBitstreamFeatures { +typedef struct { int width; // Width in pixels, as read from the bitstream. int height; // Height in pixels, as read from the bitstream. int has_alpha; // True if the bitstream contains an alpha channel. @@ -403,7 +377,7 @@ struct WebPBitstreamFeatures { int rotate; // TODO(later) int uv_sampling; // should be 0 for now. TODO(later) uint32_t pad[3]; // padding for later use -}; +} WebPBitstreamFeatures; // Internal, version-checked, entry point WEBP_EXTERN(VP8StatusCode) WebPGetFeaturesInternal( @@ -421,7 +395,7 @@ static WEBP_INLINE VP8StatusCode WebPGetFeatures( } // Decoding options -struct WebPDecoderOptions { +typedef struct { int bypass_filtering; // if true, skip the in-loop filtering int no_fancy_upsampling; // if true, use faster pointwise upsampler int use_cropping; // if true, cropping is applied _first_ @@ -436,14 +410,14 @@ struct WebPDecoderOptions { int force_rotation; // forced rotation (to be applied _last_) int no_enhancement; // if true, discard enhancement layer uint32_t pad[6]; // padding for later use -}; +} WebPDecoderOptions; // Main object storing the configuration for advanced decoding. -struct WebPDecoderConfig { +typedef struct { WebPBitstreamFeatures input; // Immutable bitstream features (optional) WebPDecBuffer output; // Output buffer (can point to external mem) WebPDecoderOptions options; // Decoding options -}; +} WebPDecoderConfig; // Internal, version-checked, entry point WEBP_EXTERN(int) WebPInitDecoderConfigInternal(WebPDecoderConfig*, int); |