1 // Copyright 2009 Google Inc. 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // http://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 // This is branched from AOSP's frameworks/base/opengl/include/ETC1/etc1.h 16 // 17 // It has been modified to implement Chromium's ETC1 API. The decoding path 18 // has been removed as we do not require it. 19 20 #ifndef THIRD_PARTY_ANDROID_OPENGL_ETC1_ETC1_H_ 21 #define THIRD_PARTY_ANDROID_OPENGL_ETC1_ETC1_H_ 22 23 // Return the size of the encoded image data. 24 25 unsigned int etc1_get_encoded_data_size(unsigned int width, unsigned int height); 26 27 // Encode an entire image. 28 // pIn - pointer to the image data. Formatted such that 29 // pixel (x,y) is at pIn + pixelSize * x + stride * y; 30 // pOut - pointer to encoded data. Must be large enough to store entire encoded image. 31 // pixelSize can be 2 or 3. 2 is an GL_UNSIGNED_SHORT_5_6_5 image, 3 is a GL_BYTE RGB image. 32 // returns non-zero if there is an error. 33 34 bool etc1_encode_image(const unsigned char* pIn, unsigned int width, unsigned int height, 35 unsigned int pixelSize, unsigned int stride, unsigned char* pOut, unsigned int outWidth, 36 unsigned int outHeight); 37 38 // Decode an entire image. 39 // pIn - pointer to encoded data. 40 // pOut - pointer to the image data. Will be written such that 41 // pixel (x,y) is at pIn + pixelSize * x + stride * y. Must be 42 // large enough to store entire image. 43 // pixelSize can be 2 or 3. 2 is an GL_UNSIGNED_SHORT_5_6_5 image, 3 is a GL_BYTE RGB image. 44 // returns false if there is an error. 45 46 bool etc1_decode_image(const unsigned char* pIn, unsigned char* pOut, 47 unsigned int width, unsigned int height, 48 unsigned int pixelSize, unsigned int stride); 49 50 // Size of a PKM header, in bytes. 51 52 #define ETC_PKM_HEADER_SIZE 16 53 54 // Format a PKM header 55 56 void etc1_pkm_format_header(unsigned char* pHeader, unsigned int width, unsigned int height); 57 58 // Check if a PKM header is correctly formatted. 59 60 bool etc1_pkm_is_valid(const unsigned char* pHeader); 61 62 // Read the image width from a PKM header 63 64 unsigned int etc1_pkm_get_width(const unsigned char* pHeader); 65 66 // Read the image height from a PKM header 67 68 unsigned int etc1_pkm_get_height(const unsigned char* pHeader); 69 70 #endif // THIRD_PARTY_ANDROID_OPENGL_ETC1_ETC1_H_ 71