| // basisu_transcoder.h |
| // Copyright (C) 2019 Binomial LLC. All Rights Reserved. |
| // Important: If compiling with gcc, be sure strict aliasing is disabled: -fno-strict-aliasing |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| #pragma once |
| |
| // Set BASISU_DEVEL_MESSAGES to 1 to enable debug printf()'s whenever an error occurs, for easier debugging during development. |
| //#define BASISU_DEVEL_MESSAGES 1 |
| |
| #include "basisu_transcoder_internal.h" |
| #include "basisu_global_selector_palette.h" |
| #include "basisu_file_headers.h" |
| |
| namespace basist |
| { |
| // High-level composite texture formats supported by the transcoder. |
| // Each of these texture formats directly correspond to OpenGL/D3D/Vulkan etc. texture formats. |
| // Notes: |
| // - If you specify a texture format that supports alpha, but the .basis file doesn't have alpha, the transcoder will automatically output a |
| // fully opaque (255) alpha channel. |
| // - The PVRTC1 texture formats only support power of 2 dimension .basis files, but this may be relaxed in a future version. |
| // - The PVRTC1 transcoders are real-time encoders, so don't expect the highest quality. We may add a slower encoder with improved quality. |
| enum transcoder_texture_format |
| { |
| // Compressed formats |
| |
| // ETC1-2 |
| cTFETC1, // Opaque only, returns RGB or alpha data if cDecodeFlagsTranscodeAlphaDataToOpaqueFormats flag is specified |
| cTFETC2, // Opaque+alpha, ETC2_EAC_A8 block followed by a ETC1 block, alpha channel will be opaque for opaque .basis files |
| |
| // BC1-5, BC7 |
| cTFBC1, // Opaque only, no punchthrough alpha support yet, transcodes alpha slice if cDecodeFlagsTranscodeAlphaDataToOpaqueFormats flag is specified |
| cTFBC3, // Opaque+alpha, BC4 followed by a BC1 block, alpha channel will be opaque for opaque .basis files |
| cTFBC4, // Red only, alpha slice is transcoded to output if cDecodeFlagsTranscodeAlphaDataToOpaqueFormats flag is specified |
| cTFBC5, // XY: Two BC4 blocks, X=R and Y=Alpha, .basis file should have alpha data (if not Y will be all 255's) |
| cTFBC7_M6_OPAQUE_ONLY, // Opaque only, RGB or alpha if cDecodeFlagsTranscodeAlphaDataToOpaqueFormats flag is specified. Highest quality of all the non-ETC1 formats. |
| cTFBC7_M5, // Opaque+alpha, alpha channel will be opaque for opaque .basis files |
| |
| // PVRTC1 4bpp |
| cTFPVRTC1_4_RGB, // Opaque only, RGB or alpha if cDecodeFlagsTranscodeAlphaDataToOpaqueFormats flag is specified, nearly lowest quality of any texture format. |
| cTFPVRTC1_4_RGBA, // Opaque+alpha, most useful for simple opacity maps. If .basis file doens't have alpha cTFPVRTC1_4_RGB will be used instead. Lowest quality of any supported texture format. |
| |
| // ASTC |
| cTFASTC_4x4, // Opaque+alpha, ASTC 4x4, alpha channel will be opaque for opaque .basis files. Transcoder uses RGB/RGBA/L/LA modes, void extent, and up to two ([0,47] and [0,255]) endpoint precisions. |
| |
| // ATC |
| cTFATC_RGB, // Opaque, RGB or alpha if cDecodeFlagsTranscodeAlphaDataToOpaqueFormats flag is specified. ATI ATC (GL_ATC_RGB_AMD) |
| cTFATC_RGBA_INTERPOLATED_ALPHA, // Opaque+alpha, alpha channel will be opaque for opaque .basis files. ATI ATC (ATC_RGBA_INTERPOLATED_ALPHA_AMD) |
| |
| cTFTotalBlockTextureFormats, |
| |
| // Uncompressed (raw pixel) formats |
| cTFRGBA32 = cTFTotalBlockTextureFormats, // 32bpp RGBA image stored in raster (not block) order in memory, R is first byte, A is last byte. |
| cTFRGB565, // 166pp RGB image stored in raster (not block) order in memory, R at bit position 11 |
| cTFBGR565, // 16bpp RGB image stored in raster (not block) order in memory, R at bit position 0 |
| cTFRGBA4444, // 16bpp RGBA image stored in raster (not block) order in memory, R at bit position 12, A at bit position 0 |
| |
| cTFTotalTextureFormats |
| }; |
| |
| uint32_t basis_get_bytes_per_block(transcoder_texture_format fmt); |
| const char* basis_get_format_name(transcoder_texture_format fmt); |
| bool basis_transcoder_format_has_alpha(transcoder_texture_format fmt); |
| basisu::texture_format basis_get_basisu_texture_format(transcoder_texture_format fmt); |
| const char* basis_get_texture_type_name(basis_texture_type tex_type); |
| bool basis_transcoder_format_is_uncompressed(transcoder_texture_format tex_type); |
| bool basis_block_format_is_uncompressed(block_format tex_type); |
| uint32_t basis_get_uncompressed_bytes_per_pixel(transcoder_texture_format fmt); |
| |
| class basisu_transcoder; |
| |
| // This struct holds all state used during transcoding. For video, it needs to persist between image transcodes (it holds the previous frame). |
| // For threading you can use one state per thread. |
| struct basisu_transcoder_state |
| { |
| struct block_preds |
| { |
| uint16_t m_endpoint_index; |
| uint8_t m_pred_bits; |
| }; |
| |
| std::vector<block_preds> m_block_endpoint_preds[2]; |
| |
| enum { cMaxPrevFrameLevels = 16 }; |
| std::vector<uint32_t> m_prev_frame_indices[2][cMaxPrevFrameLevels]; // [alpha_flag][level_index] |
| }; |
| |
| // Low-level helper class that does the actual transcoding. |
| class basisu_lowlevel_transcoder |
| { |
| friend class basisu_transcoder; |
| |
| public: |
| basisu_lowlevel_transcoder(const basist::etc1_global_selector_codebook *pGlobal_sel_codebook); |
| |
| bool decode_palettes( |
| uint32_t num_endpoints, const uint8_t *pEndpoints_data, uint32_t endpoints_data_size, |
| uint32_t num_selectors, const uint8_t *pSelectors_data, uint32_t selectors_data_size); |
| |
| bool decode_tables(const uint8_t *pTable_data, uint32_t table_data_size); |
| |
| bool transcode_slice(void *pDst_blocks, uint32_t num_blocks_x, uint32_t num_blocks_y, const uint8_t *pImage_data, uint32_t image_data_size, block_format fmt, |
| uint32_t output_block_or_pixel_stride_in_bytes, bool wrap_addressing, bool bc1_allow_threecolor_blocks, const basis_file_header &header, const basis_slice_desc& slice_desc, uint32_t output_row_pitch_in_blocks_or_pixels = 0, |
| basisu_transcoder_state *pState = nullptr, bool astc_transcode_alpha = false, void* pAlpha_blocks = nullptr, uint32_t output_rows_in_pixels = 0); |
| |
| private: |
| typedef std::vector<endpoint> endpoint_vec; |
| endpoint_vec m_endpoints; |
| |
| typedef std::vector<selector> selector_vec; |
| selector_vec m_selectors; |
| |
| const etc1_global_selector_codebook *m_pGlobal_sel_codebook; |
| |
| huffman_decoding_table m_endpoint_pred_model, m_delta_endpoint_model, m_selector_model, m_selector_history_buf_rle_model; |
| |
| uint32_t m_selector_history_buf_size; |
| |
| basisu_transcoder_state m_def_state; |
| }; |
| |
| struct basisu_slice_info |
| { |
| uint32_t m_orig_width; |
| uint32_t m_orig_height; |
| |
| uint32_t m_width; |
| uint32_t m_height; |
| |
| uint32_t m_num_blocks_x; |
| uint32_t m_num_blocks_y; |
| uint32_t m_total_blocks; |
| |
| uint32_t m_compressed_size; |
| |
| uint32_t m_slice_index; // the slice index in the .basis file |
| uint32_t m_image_index; // the source image index originally provided to the encoder |
| uint32_t m_level_index; // the mipmap level within this image |
| |
| uint32_t m_unpacked_slice_crc16; |
| |
| bool m_alpha_flag; // true if the slice has alpha data |
| bool m_iframe_flag; // true if the slice is an I-Frame |
| }; |
| |
| typedef std::vector<basisu_slice_info> basisu_slice_info_vec; |
| |
| struct basisu_image_info |
| { |
| uint32_t m_image_index; |
| uint32_t m_total_levels; |
| |
| uint32_t m_orig_width; |
| uint32_t m_orig_height; |
| |
| uint32_t m_width; |
| uint32_t m_height; |
| |
| uint32_t m_num_blocks_x; |
| uint32_t m_num_blocks_y; |
| uint32_t m_total_blocks; |
| |
| uint32_t m_first_slice_index; |
| |
| bool m_alpha_flag; // true if the image has alpha data |
| bool m_iframe_flag; // true if the image is an I-Frame |
| }; |
| |
| struct basisu_image_level_info |
| { |
| uint32_t m_image_index; |
| uint32_t m_level_index; |
| |
| uint32_t m_orig_width; |
| uint32_t m_orig_height; |
| |
| uint32_t m_width; |
| uint32_t m_height; |
| |
| uint32_t m_num_blocks_x; |
| uint32_t m_num_blocks_y; |
| uint32_t m_total_blocks; |
| |
| uint32_t m_first_slice_index; |
| |
| bool m_alpha_flag; // true if the image has alpha data |
| bool m_iframe_flag; // true if the image is an I-Frame |
| }; |
| |
| struct basisu_file_info |
| { |
| uint32_t m_version; |
| uint32_t m_total_header_size; |
| |
| uint32_t m_total_selectors; |
| uint32_t m_selector_codebook_size; |
| |
| uint32_t m_total_endpoints; |
| uint32_t m_endpoint_codebook_size; |
| |
| uint32_t m_tables_size; |
| uint32_t m_slices_size; |
| |
| basis_texture_type m_tex_type; |
| uint32_t m_us_per_frame; |
| |
| // Low-level slice information (1 slice per image for color-only basis files, 2 for alpha basis files) |
| basisu_slice_info_vec m_slice_info; |
| |
| uint32_t m_total_images; // total # of images |
| std::vector<uint32_t> m_image_mipmap_levels; // the # of mipmap levels for each image |
| |
| uint32_t m_userdata0; |
| uint32_t m_userdata1; |
| |
| bool m_etc1s; // always true for basis universal |
| bool m_y_flipped; // true if the image was Y flipped |
| bool m_has_alpha_slices; // true if the texture has alpha slices (even slices RGB, odd slices alpha) |
| }; |
| |
| // High-level transcoder class which accepts .basis file data and allows the caller to query information about the file and transcode image levels to various texture formats. |
| // If you're just starting out this is the class you care about. |
| class basisu_transcoder |
| { |
| basisu_transcoder(basisu_transcoder&); |
| basisu_transcoder& operator= (const basisu_transcoder&); |
| |
| public: |
| basisu_transcoder(const etc1_global_selector_codebook *pGlobal_sel_codebook); |
| |
| // Validates the .basis file. This computes a crc16 over the entire file, so it's slow. |
| bool validate_file_checksums(const void *pData, uint32_t data_size, bool full_validation) const; |
| |
| // Quick header validation - no crc16 checks. |
| bool validate_header(const void *pData, uint32_t data_size) const; |
| |
| basis_texture_type get_texture_type(const void *pData, uint32_t data_size) const; |
| bool get_userdata(const void *pData, uint32_t data_size, uint32_t &userdata0, uint32_t &userdata1) const; |
| |
| // Returns the total number of images in the basis file (always 1 or more). |
| // Note that the number of mipmap levels for each image may differ, and that images may have different resolutions. |
| uint32_t get_total_images(const void *pData, uint32_t data_size) const; |
| |
| // Returns the number of mipmap levels in an image. |
| uint32_t get_total_image_levels(const void *pData, uint32_t data_size, uint32_t image_index) const; |
| |
| // Returns basic information about an image. Note that orig_width/orig_height may not be a multiple of 4. |
| bool get_image_level_desc(const void *pData, uint32_t data_size, uint32_t image_index, uint32_t level_index, uint32_t &orig_width, uint32_t &orig_height, uint32_t &total_blocks) const; |
| |
| // Returns information about the specified image. |
| bool get_image_info(const void *pData, uint32_t data_size, basisu_image_info &image_info, uint32_t image_index) const; |
| |
| // Returns information about the specified image's mipmap level. |
| bool get_image_level_info(const void *pData, uint32_t data_size, basisu_image_level_info &level_info, uint32_t image_index, uint32_t level_index) const; |
| |
| // Get a description of the basis file and low-level information about each slice. |
| bool get_file_info(const void *pData, uint32_t data_size, basisu_file_info &file_info) const; |
| |
| // start_transcoding() must be called before calling transcode_slice() or transcode_image_level(). |
| // This decompresses the selector/endpoint codebooks, so ideally you would only call this once per .basis file (not each image/mipmap level). |
| bool start_transcoding(const void *pData, uint32_t data_size) const; |
| |
| // Returns true if start_transcoding() has been called. |
| bool get_ready_to_transcode() const { return m_lowlevel_decoder.m_endpoints.size() > 0; } |
| |
| enum |
| { |
| // PVRTC1: texture will use wrap addressing vs. clamp (most PVRTC viewer tools assume wrap addressing, so we default to wrap although that can cause edge artifacts) |
| cDecodeFlagsPVRTCWrapAddressing = 1, |
| |
| // PVRTC1: decode non-pow2 ETC1S texture level to the next larger power of 2 (not implemented yet, but we're going to support it). Ignored if the slice's dimensions are already a power of 2. |
| cDecodeFlagsPVRTCDecodeToNextPow2 = 2, |
| |
| // When decoding to an opaque texture format, if the basis file has alpha, decode the alpha slice instead of the color slice to the output texture format. |
| // This is primarily to allow decoding of textures with alpha to multiple ETC1 textures (one for color, another for alpha). |
| cDecodeFlagsTranscodeAlphaDataToOpaqueFormats = 4, |
| |
| // Forbid usage of BC1 3 color blocks (we don't support BC1 punchthrough alpha yet). |
| // This flag is used internally when decoding to BC3. |
| cDecodeFlagsBC1ForbidThreeColorBlocks = 8, |
| |
| // The output buffer contains alpha endpoint/selector indices. |
| // Used internally when decoding formats like ASTC that require both color and alpha data to be available when transcoding to the output format. |
| cDecodeFlagsOutputHasAlphaIndices = 16, |
| }; |
| |
| // transcode_image_level() decodes a single mipmap level from the .basis file to any of the supported output texture formats. |
| // It'll first find the slice(s) to transcode, then call transcode_slice() one or two times to decode both the color and alpha texture data (or RG texture data from two slices for BC5). |
| // If the .basis file doesn't have alpha slices, the output alpha blocks will be set to fully opaque (all 255's). |
| // Currently, to decode to PVRTC1 the basis texture's dimensions in pixels must be a power of 2, due to PVRTC1 format requirements. |
| // output_blocks_buf_size_in_blocks_or_pixels should be at least the image level's total_blocks (num_blocks_x * num_blocks_y), or the total number of output pixels if fmt==cTFRGBA32. |
| // output_row_pitch_in_blocks_or_pixels: Number of blocks or pixels per row. If 0, the transcoder uses the slice's num_blocks_x or orig_width (NOT num_blocks_x * 4). Ignored for PVRTC1 (due to texture swizzling). |
| // output_rows_in_pixels: Ignored unless fmt is cRGBA32. The total number of output rows in the output buffer. If 0, the transcoder assumes the slice's orig_height (NOT num_blocks_y * 4). |
| // Notes: |
| // - basisu_transcoder_init() must have been called first to initialize the transcoder lookup tables before calling this function. |
| // - This method assumes the output texture buffer is readable. In some cases to handle alpha, the transcoder will write temporary data to the output texture in |
| // a first pass, which will be read in a second pass. |
| bool transcode_image_level( |
| const void *pData, uint32_t data_size, |
| uint32_t image_index, uint32_t level_index, |
| void *pOutput_blocks, uint32_t output_blocks_buf_size_in_blocks_or_pixels, |
| transcoder_texture_format fmt, |
| uint32_t decode_flags = cDecodeFlagsPVRTCWrapAddressing, uint32_t output_row_pitch_in_blocks_or_pixels = 0, basisu_transcoder_state *pState = nullptr, uint32_t output_rows_in_pixels = 0) const; |
| |
| // Finds the basis slice corresponding to the specified image/level/alpha params, or -1 if the slice can't be found. |
| int find_slice(const void *pData, uint32_t data_size, uint32_t image_index, uint32_t level_index, bool alpha_data) const; |
| |
| // transcode_slice() decodes a single slice from the .basis file. It's a low-level API - most likely you want to use transcode_image_level(). |
| // This is a low-level API, and will be needed to be called multiple times to decode some texture formats (like BC3, BC5, or ETC2). |
| // output_blocks_buf_size_in_blocks_or_pixels is just used for verification to make sure the output buffer is large enough. |
| // output_blocks_buf_size_in_blocks_or_pixels should be at least the image level's total_blocks (num_blocks_x * num_blocks_y), or the total number of output pixels if fmt==cTFRGBA32. |
| // output_block_stride_in_bytes: Number of bytes between each output block. |
| // output_row_pitch_in_blocks_or_pixels: Number of blocks or pixels per row. If 0, the transcoder uses the slice's num_blocks_x or orig_width (NOT num_blocks_x * 4). Ignored for PVRTC1 (due to texture swizzling). |
| // output_rows_in_pixels: Ignored unless fmt is cRGBA32. The total number of output rows in the output buffer. If 0, the transcoder assumes the slice's orig_height (NOT num_blocks_y * 4). |
| // Notes: |
| // - basisu_transcoder_init() must have been called first to initialize the transcoder lookup tables before calling this function. |
| bool transcode_slice(const void *pData, uint32_t data_size, uint32_t slice_index, |
| void *pOutput_blocks, uint32_t output_blocks_buf_size_in_blocks_or_pixels, |
| block_format fmt, uint32_t output_block_stride_in_bytes, uint32_t decode_flags = cDecodeFlagsPVRTCWrapAddressing, uint32_t output_row_pitch_in_blocks_or_pixels = 0, basisu_transcoder_state * pState = nullptr, void* pAlpha_blocks = nullptr, uint32_t output_rows_in_pixels = 0) const; |
| |
| private: |
| mutable basisu_lowlevel_transcoder m_lowlevel_decoder; |
| |
| int find_first_slice_index(const void* pData, uint32_t data_size, uint32_t image_index, uint32_t level_index) const; |
| |
| bool validate_header_quick(const void* pData, uint32_t data_size) const; |
| }; |
| |
| // basisu_transcoder_init() must be called before a .basis file can be transcoded. |
| void basisu_transcoder_init(); |
| |
| enum debug_flags_t |
| { |
| cDebugFlagVisCRs = 1, |
| cDebugFlagVisBC1Sels = 2, |
| cDebugFlagVisBC1Endpoints = 4 |
| }; |
| uint32_t get_debug_flags(); |
| void set_debug_flags(uint32_t f); |
| |
| } // namespace basisu |