libwebp-0.3.1

third_party/libwebp/webp/decode.h

 // Copyright 2010 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/
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
 // -----------------------------------------------------------------------------
 //
 //  Main decoding functions for WebP images.
 //
 // Author: Skal (pascal.massimino@gmail.com)
 
 #ifndef WEBP_WEBP_DECODE_H_
 #define WEBP_WEBP_DECODE_H_
 
 #include "./types.h"
 
 #if defined(__cplusplus) || defined(c_plusplus)
 extern "C" {
 #endif
 
 #define WEBP_DECODER_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 VP8StatusCode VP8StatusCode;
+// typedef enum WEBP_CSP_MODE WEBP_CSP_MODE;
 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);
 
 // Retrieve basic header information: width, height.
@@ skipping 91 matching lines @@
 // 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 {
+typedef 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
-};
+} WEBP_CSP_MODE;
 
 // Some useful macros:
 static WEBP_INLINE int WebPIsPremultipliedMode(WEBP_CSP_MODE mode) {
   return (mode == MODE_rgbA || mode == MODE_bgrA || mode == MODE_Argb ||
           mode == MODE_rgbA_4444);
 }
 
 static WEBP_INLINE int WebPIsAlphaMode(WEBP_CSP_MODE mode) {
   return (mode == MODE_RGBA || mode == MODE_BGRA || mode == MODE_ARGB ||
           mode == MODE_RGBA_4444 || mode == MODE_YUVA ||
@@ skipping 48 matching lines @@
   return WebPInitDecBufferInternal(buffer, WEBP_DECODER_ABI_VERSION);
 }
 
 // Free any memory associated with the buffer. Must always be called last.
 // Note: doesn't free the 'buffer' structure itself.
 WEBP_EXTERN(void) WebPFreeDecBuffer(WebPDecBuffer* buffer);
 
 //------------------------------------------------------------------------------
 // Enumeration of the status codes
 
-enum VP8StatusCode {
+typedef enum VP8StatusCode {
   VP8_STATUS_OK = 0,
   VP8_STATUS_OUT_OF_MEMORY,
   VP8_STATUS_INVALID_PARAM,
   VP8_STATUS_BITSTREAM_ERROR,
   VP8_STATUS_UNSUPPORTED_FEATURE,
   VP8_STATUS_SUSPENDED,
   VP8_STATUS_USER_ABORT,
   VP8_STATUS_NOT_ENOUGH_DATA
-};
+} VP8StatusCode;
 
 //------------------------------------------------------------------------------
 // Incremental decoding
 //
 // This API allows streamlined decoding of partial data.
 // Picture can be incrementally decoded as data become available thanks to the
 // WebPIDecoder object. This object can be left in a SUSPENDED state if the
 // picture is only partially decoded, pending additional input.
 // Code example:
 //
@@ skipping 12 matching lines @@
 //     // Part of the image can now be refreshed by calling to
 //     // WebPIDecGetRGB()/WebPIDecGetYUVA() etc.
 //   }
 //   WebPIDelete(idec);
 
 // 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'
 // is kept, which means that the lifespan of 'output_buffer' must be larger than
 // that of the returned WebPIDecoder object.
+// The supplied 'output_buffer' content MUST NOT be changed between calls to
+// WebPIAppend() or WebPIUpdate() unless 'output_buffer.is_external_memory' is
+// set to 1. In such a case, it is allowed to modify the pointers, size and
+// stride of output_buffer.u.RGBA or output_buffer.u.YUVA, provided they remain
+// within valid bounds.
+// All other fields of WebPDecBuffer MUST remain constant between calls.
 // Returns NULL if the allocation failed.
 WEBP_EXTERN(WebPIDecoder*) WebPINewDecoder(WebPDecBuffer* output_buffer);
 
 // This function allocates and initializes an incremental-decoder object, which
 // 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
@@ skipping 198 matching lines @@
 // 'config' into account. Returns decoding status (which should be VP8_STATUS_OK
 // if the decoding was successful).
 WEBP_EXTERN(VP8StatusCode) WebPDecode(const uint8_t* data, size_t data_size,
                                       WebPDecoderConfig* config);
 
 #if defined(__cplusplus) || defined(c_plusplus)
 }    // extern "C"
 #endif
 
 #endif  /* WEBP_WEBP_DECODE_H_ */