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@ -0,0 +1,565 @@ |
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/* |
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HOW TO USE: |
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In exactly one translation unit (.c or .cpp file), #define MSF_GIF_IMPL before including the header, like so: |
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#define MSF_GIF_IMPL |
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#include "msf_gif.h" |
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Everywhere else, just include the header like normal. |
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USAGE EXAMPLE: |
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int width = 480, height = 320, centisecondsPerFrame = 5, bitDepth = 16; |
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MsfGifState gifState = {}; |
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msf_gif_begin(&gifState, "example.gif", width, height); |
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msf_gif_frame(&gifState, ..., centisecondsPerFrame, bitDepth, width * 4); //frame 1 |
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msf_gif_frame(&gifState, ..., centisecondsPerFrame, bitDepth, width * 4); //frame 2 |
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msf_gif_frame(&gifState, ..., centisecondsPerFrame, bitDepth, width * 4); //frame 3, etc... |
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msf_gif_end(&gifState); |
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Detailed function documentation can be found in the header section below. |
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REPLACING MALLOC AND FWRITE: |
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This library uses malloc+free internally for memory allocation and fopen+fwrite+fclose for file output. |
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To facilitate custom memory management and I/O, these calls go through macros, which can be redefined. |
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In order to replace them, simply #define the relevant macros in the same place where you #define MSF_GIF_IMPL. |
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The macros are: MSF_GIF_MALLOC, MSF_GIF_FREE, MSF_GIF_FOPEN, MSF_GIF_FWRITE, MSF_GIF_FCLOSE. |
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Search for their default definitions below to see the exactly what arguments they take. |
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If your allocator needs a context pointer, you can set the `customAllocatorContext` field of the MsfGifState struct |
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before calling msf_gif_begin(), and it will be passed to all subsequent allocator macro calls. |
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The same goes for file I/O macros, using the `customOutputContext` field. |
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See end of file for license information. |
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*/ |
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//version 1.2 |
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#ifndef MSF_GIF_H |
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#define MSF_GIF_H |
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#include <stdint.h> |
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#include <stddef.h> |
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typedef struct { |
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uint32_t * pixels; |
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uint8_t * used; |
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int depth, count, rbits, gbits, bbits; |
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} MsfCookedFrame; |
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typedef struct { |
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void * fp; |
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MsfCookedFrame previousFrame; |
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int width, height; |
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int totalBytesWritten; |
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void * customAllocatorContext; |
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void * customOutputContext; |
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} MsfGifState; |
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#ifdef __cplusplus |
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extern "C" { |
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#endif //__cplusplus |
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/** |
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* @param outputFilePath Relative path to the output file, as a null-terminated string of UTF-8 bytes. |
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* @param width Image width in pixels - must be the same for the whole gif. |
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* @param height Image height in pixels - must be the same for the whole gif. |
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* @return The size of the file written so far, or 0 on error. |
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*/ |
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size_t msf_gif_begin(MsfGifState * handle, const char * outputFilePath, int width, int height); |
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/** |
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* @param pixelData Pointer to raw framebuffer data. Rows must be contiguous in memory, in RGBA8 format. |
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* Note: This function does NOT free `pixelData`. You must free it yourself afterwards. |
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* @param centiSecondsPerFrame How many hundredths of a second this frame should be displayed for. |
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* Note: This being specified in centiseconds is a limitation of the GIF format. |
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* @param maxBitDepth Limits how many bits per pixel can be used when quantizing the gif. |
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* The actual bit depth chosen for a given frame will be less than or equal to |
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* the supplied maximum, depending on the variety of colors used in the frame. |
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* `maxBitDepth` will be clamped between 1 and 16. The recommended default is 16. |
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* Lowering this value can result in faster exports and smaller gifs, |
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* but the quality may suffer. |
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* Please experiment with this value to find what works best for your application. |
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* @param pitchInBytes The number of bytes from the beginning of one row of pixels to the beginning of the next. |
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* If you want to flip the image, just pass in a negative pitch. |
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* @return The size of the file written so far, or 0 on error. |
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*/ |
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size_t msf_gif_frame(MsfGifState * handle, |
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uint8_t * pixelData, int centiSecondsPerFame, int maxBitDepth, int pitchInBytes); |
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/** |
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* @return The size of the written file in bytes, or 0 on error. |
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*/ |
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size_t msf_gif_end(MsfGifState * handle); |
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#ifdef __cplusplus |
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} |
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#endif //__cplusplus |
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#endif //MSF_GIF_H |
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//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// |
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/// IMPLEMENTATION /// |
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//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// |
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#ifdef MSF_GIF_IMPL |
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#ifndef MSF_GIF_ALREADY_IMPLEMENTED_IN_THIS_TRANSLATION_UNIT |
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#define MSF_GIF_ALREADY_IMPLEMENTED_IN_THIS_TRANSLATION_UNIT |
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//ensure the library user has either defined both of malloc/free, or neither |
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#if defined(MSF_GIF_MALLOC) && defined(MSF_GIF_FREE) |
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#elif !defined(MSF_GIF_MALLOC) && !defined(MSF_GIF_FREE) |
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#else |
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#error "You must either define both MSF_GIF_MALLOC and MSF_GIF_FREE, or define neither of them" |
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#endif |
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//provide default allocator definitions that redirect to the standard global allocator |
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#if !defined(MSF_GIF_MALLOC) |
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#include <stdlib.h> //malloc, etc. |
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#define MSF_GIF_MALLOC(contextPointer, newSize) malloc(newSize) |
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#define MSF_GIF_FREE(contextPointer, oldMemory, oldSize) free(oldMemory) |
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#endif |
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//ensure the library user has either defined all of fopen/fwrite/fclose, or none |
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#if defined(MSF_GIF_FOPEN) && defined(MSF_GIF_FWRITE) && defined(MSF_GIF_FCLOSE) |
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#elif !defined(MSF_GIF_FOPEN) && !defined(MSF_GIF_FWRITE) && !defined(MSF_GIF_FCLOSE) |
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#else |
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#error "You must either define all of MSF_GIF_FOPEN, MSF_GIF_FWRITE, and MSF_GIF_FCLOSE, or define none of them" |
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#endif |
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//provide default file ops that redirect to the standard library ones |
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#if !defined(MSF_GIF_FOPEN) |
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#include <stdio.h> //FILE ops (fopen, etc.) |
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#define MSF_GIF_FOPEN(contextPointer, filePath) fopen(filePath, "wb") |
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#define MSF_GIF_FWRITE(contextPointer, filePointer, data, dataSize) fwrite(data, dataSize, 1, (FILE *) filePointer) |
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#define MSF_GIF_FCLOSE(contextPointer, filePointer) fclose((FILE *) filePointer) |
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#endif |
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//instrumentation for capturing profiling traces (useless for the library user, but useful for the library author) |
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#ifdef MSF_GIF_ENABLE_TRACING |
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#define MsfTimeFunc TimeFunc |
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#define MsfTimeLoop TimeLoop |
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#define msf_init_profiling_thread init_profiling_thread |
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#else |
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#define MsfTimeFunc |
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#define MsfTimeLoop(name) |
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#define msf_init_profiling_thread() |
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#endif //MSF_GIF_ENABLE_TRACING |
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#include <string.h> //memcpy |
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//TODO: use compiler-specific notation to force-inline functions currently marked inline |
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#if defined(__GNUC__) //gcc, clang |
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static inline int msf_bit_log(int i) { return 32 - __builtin_clz(i); } |
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#elif defined(_MSC_VER) //msvc |
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#include <intrin.h> |
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static inline int msf_bit_log(int i) { unsigned long idx; _BitScanReverse(&idx, i); return idx + 1; } |
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#else //fallback implementation for other compilers |
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//from https://stackoverflow.com/a/31718095/3064745 - thanks! |
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static inline int msf_bit_log(int i) { |
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static const int MultiplyDeBruijnBitPosition[32] = { |
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0, 9, 1, 10, 13, 21, 2, 29, 11, 14, 16, 18, 22, 25, 3, 30, |
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8, 12, 20, 28, 15, 17, 24, 7, 19, 27, 23, 6, 26, 5, 4, 31, |
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}; |
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i |= i >> 1; |
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i |= i >> 2; |
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i |= i >> 4; |
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i |= i >> 8; |
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i |= i >> 16; |
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return MultiplyDeBruijnBitPosition[(uint32_t)(i * 0x07C4ACDDU) >> 27] + 1; |
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} |
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#endif |
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static inline int msf_imin(int a, int b) { return a < b? a : b; } |
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static inline int msf_imax(int a, int b) { return b < a? a : b; } |
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//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// |
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/// Frame Cooking /// |
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//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// |
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#if (defined (__SSE2__) || defined (_M_X64) || _M_IX86_FP == 2) && !defined(MSF_GIF_NO_SSE2) |
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#include <emmintrin.h> |
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#endif |
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static const int msfUsedAllocSize = (1 << 16) * sizeof(uint8_t); |
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static MsfCookedFrame msf_cook_frame(void * allocContext, int width, int height, int pitch, int depth, uint8_t * raw) |
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{ MsfTimeFunc |
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MsfCookedFrame blank = {0}; |
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//bit depth for each channel |
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const static int rdepths[17] = { 0, 0, 1, 1, 1, 2, 2, 2, 3, 3, 3, 4, 4, 4, 5, 5, 5 }; |
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const static int gdepths[17] = { 0, 1, 1, 1, 2, 2, 2, 3, 3, 3, 4, 4, 4, 5, 5, 5, 6 }; |
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const static int bdepths[17] = { 0, 0, 0, 1, 1, 1, 2, 2, 2, 3, 3, 3, 4, 4, 4, 5, 5 }; |
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const static int ditherKernel[16] = { |
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0 << 12, 8 << 12, 2 << 12, 10 << 12, |
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12 << 12, 4 << 12, 14 << 12, 6 << 12, |
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3 << 12, 11 << 12, 1 << 12, 9 << 12, |
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15 << 12, 7 << 12, 13 << 12, 5 << 12, |
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}; |
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uint8_t * used = (uint8_t *) MSF_GIF_MALLOC(allocContext, msfUsedAllocSize); |
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if (!used) return blank; |
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uint32_t * cooked = (uint32_t *) MSF_GIF_MALLOC(allocContext, width * height * sizeof(uint32_t)); |
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if (!cooked) { MSF_GIF_FREE(allocContext, used, msfUsedAllocSize); return blank; } |
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int count = 0; |
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MsfTimeLoop("do") do { |
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int rbits = rdepths[depth], gbits = gdepths[depth], bbits = bdepths[depth]; |
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int paletteSize = 1 << (rbits + gbits + bbits); |
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memset(used, 0, paletteSize * sizeof(uint8_t)); |
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//TODO: document what this math does and why it's correct |
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int rdiff = (1 << (8 - rbits)) - 1; |
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int gdiff = (1 << (8 - gbits)) - 1; |
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int bdiff = (1 << (8 - bbits)) - 1; |
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short rmul = (short) ((255.0f - rdiff) / 255.0f * 257); |
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short gmul = (short) ((255.0f - gdiff) / 255.0f * 257); |
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short bmul = (short) ((255.0f - bdiff) / 255.0f * 257); |
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int gmask = ((1 << gbits) - 1) << rbits; |
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int bmask = ((1 << bbits) - 1) << rbits << gbits; |
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MsfTimeLoop("cook") for (int y = 0; y < height; ++y) { |
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int x = 0; |
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#if (defined (__SSE2__) || defined (_M_X64) || _M_IX86_FP == 2) && !defined(MSF_GIF_NO_SSE2) |
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__m128i k = _mm_loadu_si128((__m128i *) &ditherKernel[(y & 3) * 4]); |
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__m128i k2 = _mm_or_si128(_mm_srli_epi32(k, rbits), _mm_slli_epi32(_mm_srli_epi32(k, bbits), 16)); |
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// MsfTimeLoop("SIMD") |
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for (; x < width - 3; x += 4) { |
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uint8_t * pixels = &raw[y * pitch + x * 4]; |
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__m128i p = _mm_loadu_si128((__m128i *) pixels); |
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__m128i rb = _mm_and_si128(p, _mm_set1_epi32(0x00FF00FF)); |
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__m128i rb1 = _mm_mullo_epi16(rb, _mm_set_epi16(bmul, rmul, bmul, rmul, bmul, rmul, bmul, rmul)); |
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__m128i rb2 = _mm_adds_epu16(rb1, k2); |
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__m128i r3 = _mm_srli_epi32(_mm_and_si128(rb2, _mm_set1_epi32(0x0000FFFF)), 16 - rbits); |
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__m128i b3 = _mm_and_si128(_mm_srli_epi32(rb2, 32 - rbits - gbits - bbits), _mm_set1_epi32(bmask)); |
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__m128i g = _mm_and_si128(_mm_srli_epi32(p, 8), _mm_set1_epi32(0x000000FF)); |
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__m128i g1 = _mm_mullo_epi16(g, _mm_set1_epi32(gmul)); |
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__m128i g2 = _mm_adds_epu16(g1, _mm_srli_epi32(k, gbits)); |
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__m128i g3 = _mm_and_si128(_mm_srli_epi32(g2, 16 - rbits - gbits), _mm_set1_epi32(gmask)); |
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//TODO: does storing this as a __m128i then reading it back as a uint32_t violate strict aliasing? |
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uint32_t * c = &cooked[y * width + x]; |
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__m128i out = _mm_or_si128(_mm_or_si128(r3, g3), b3); |
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_mm_storeu_si128((__m128i *) c, out); |
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} |
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#endif |
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//scalar cleanup loop |
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// MsfTimeLoop("scalar") |
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for (; x < width; ++x) { |
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uint8_t * p = &raw[y * pitch + x * 4]; |
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int dx = x & 3, dy = y & 3; |
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int k = ditherKernel[dy * 4 + dx]; |
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cooked[y * width + x] = |
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(msf_imin(65535, p[2] * bmul + (k >> bbits)) >> (16 - rbits - gbits - bbits) & bmask) | |
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(msf_imin(65535, p[1] * gmul + (k >> gbits)) >> (16 - rbits - gbits ) & gmask) | |
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msf_imin(65535, p[0] * rmul + (k >> rbits)) >> (16 - rbits ); |
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} |
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} |
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count = 0; |
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MsfTimeLoop("mark and count") for (int i = 0; i < width * height; ++i) { |
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used[cooked[i]] = 1; |
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} |
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//count used colors |
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MsfTimeLoop("count") for (int j = 0; j < paletteSize; ++j) { |
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count += used[j]; |
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} |
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} while (count >= 256 && --depth); |
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MsfCookedFrame ret = { cooked, used, depth, count, rdepths[depth], gdepths[depth], bdepths[depth] }; |
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return ret; |
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} |
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//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// |
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/// MsfFileBuffer /// |
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//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// |
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typedef struct { |
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uint8_t * block; |
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uint8_t * head; |
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uint8_t * end; |
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} MsfFileBuffer; |
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static inline void msf_fb_write_data(MsfFileBuffer * buf, void * data, size_t bytes) { |
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memcpy(buf->head, data, bytes); |
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buf->head += bytes; |
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} |
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static MsfFileBuffer msf_create_file_buffer(void * allocContext, size_t bytes) { |
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uint8_t * block = (uint8_t *) MSF_GIF_MALLOC(allocContext, bytes); |
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MsfFileBuffer ret = { block, block, block + bytes }; |
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return ret; |
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} |
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//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// |
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/// Frame Compression /// |
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//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// |
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static inline int msf_put_code(MsfFileBuffer * buf, uint32_t * blockBits, int len, uint32_t code) { |
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//insert new code into block buffer |
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int idx = *blockBits / 8; |
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int bit = *blockBits % 8; |
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buf->head[idx + 0] |= code << bit ; |
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buf->head[idx + 1] |= code >> ( 8 - bit); |
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buf->head[idx + 2] |= code >> (16 - bit); |
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*blockBits += len; |
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//prep the next block buffer if the current one is full |
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if (*blockBits >= 256 * 8) { |
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*blockBits -= 255 * 8; |
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buf->head += 256; |
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buf->head[2] = buf->head[1]; |
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buf->head[1] = buf->head[0]; |
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buf->head[0] = 255; |
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memset(buf->head + 4, 0, 256); |
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} |
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return 1; |
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} |
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typedef struct { |
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int16_t * data; |
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int len; |
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int stride; |
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} MsfStridedList; |
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static inline void msf_lzw_reset(MsfStridedList * lzw, int tableSize, int stride) { MsfTimeFunc |
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memset(lzw->data, 0xFF, 4096 * stride * sizeof(int16_t)); |
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lzw->len = tableSize + 2; |
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lzw->stride = stride; |
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} |
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static MsfFileBuffer msf_compress_frame(void * allocContext, int width, int height, int centiSeconds, |
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MsfCookedFrame frame, MsfCookedFrame previous) |
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{ MsfTimeFunc |
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MsfFileBuffer blank = {0}; |
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//NOTE: we allocate enough memory for the worst case upfront because it's a reasonable amount |
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// (about half the size of a CookedFrame), and prevents us from ever having to check size or realloc |
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MsfFileBuffer buf = msf_create_file_buffer(allocContext, 1024 + width * height * 2); |
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if (!buf.block) return blank; |
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int lzwAllocSize = 4096 * 256 * sizeof(int16_t); |
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MsfStridedList lzw = { (int16_t *) MSF_GIF_MALLOC(allocContext, lzwAllocSize) }; |
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if (!lzw.data) { MSF_GIF_FREE(allocContext, buf.block, buf.end - buf.block); return blank; } |
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//allocate tlb |
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int totalBits = frame.rbits + frame.gbits + frame.bbits; |
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int tlbSize = 1 << totalBits; |
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uint8_t tlb[1 << 16]; //only 64k, so stack allocating is fine |
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//generate palette |
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typedef struct { uint8_t r, g, b; } Color3; |
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Color3 table[256] = { {0} }; |
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int tableIdx = 1; //we start counting at 1 because 0 is the transparent color |
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MsfTimeLoop("table") for (int i = 0; i < tlbSize; ++i) { |
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if (frame.used[i]) { |
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tlb[i] = tableIdx; |
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int rmask = (1 << frame.rbits) - 1; |
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int gmask = (1 << frame.gbits) - 1; |
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//isolate components |
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int r = i & rmask; |
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int g = i >> frame.rbits & gmask; |
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int b = i >> (frame.rbits + frame.gbits); |
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//shift into highest bits |
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r <<= 8 - frame.rbits; |
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g <<= 8 - frame.gbits; |
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b <<= 8 - frame.bbits; |
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table[tableIdx].r = r | r >> frame.rbits | r >> (frame.rbits * 2) | r >> (frame.rbits * 3); |
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table[tableIdx].g = g | g >> frame.gbits | g >> (frame.gbits * 2) | g >> (frame.gbits * 3); |
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table[tableIdx].b = b | b >> frame.bbits | b >> (frame.bbits * 2) | b >> (frame.bbits * 3); |
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++tableIdx; |
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} |
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} |
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int tableBits = msf_bit_log(tableIdx - 1); |
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int tableSize = 1 << tableBits; |
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//NOTE: we don't just compare `depth` field here because it will be wrong for the first frame and we will segfault |
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int hasSamePal = frame.rbits == previous.rbits && frame.gbits == previous.gbits && frame.bbits == previous.bbits; |
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//NOTE: because __attribute__((__packed__)) is annoyingly compiler-specific, we do this unreadable weirdness |
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char headerBytes[19] = "\x21\xF9\x04\x05\0\0\0\0" "\x2C\0\0\0\0\0\0\0\0\x80"; |
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memcpy(&headerBytes[4], ¢iSeconds, 2); |
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memcpy(&headerBytes[13], &width, 2); |
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memcpy(&headerBytes[15], &height, 2); |
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headerBytes[17] |= tableBits - 1; |
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msf_fb_write_data(&buf, headerBytes, 18); |
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//local color table |
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msf_fb_write_data(&buf, table, tableSize * sizeof(Color3)); |
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*buf.head++ = tableBits; |
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msf_lzw_reset(&lzw, tableSize, tableIdx); |
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//prep block |
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memset(buf.head, 0, 260); |
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buf.head[0] = 255; |
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uint32_t blockBits = 8; //relative to block.head |
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int lastCode = hasSamePal && frame.pixels[0] == previous.pixels[0]? 0 : tlb[frame.pixels[0]]; |
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MsfTimeLoop("compress") for (int i = 1; i < width * height; ++i) { |
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//PERF: branching vs. branchless version of this line is observed to have no discernable impact on speed |
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int color = hasSamePal && frame.pixels[i] == previous.pixels[i]? 0 : tlb[frame.pixels[i]]; |
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//PERF: branchless version must use && otherwise it will segfault on frame 1, but it's well-predicted so OK |
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// int color = (!(hasSamePal && frame.pixels[i] == previous.pixels[i])) * tlb[frame.pixels[i]]; |
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int code = (&lzw.data[lastCode * lzw.stride])[color]; |
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if (code < 0) { |
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//write to code stream |
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int codeBits = msf_bit_log(lzw.len - 1); |
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msf_put_code(&buf, &blockBits, codeBits, lastCode); |
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//NOTE: [I THINK] we need to leave room for 2 more codes (leftover and end code) |
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// because we don't ever reset the table after writing the leftover bits |
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//Q: is my thinking correct on this one? |
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//Q: why can't we just check when writing out those codes? too verbose? can't we factor to a funtion? |
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if (lzw.len > 4094) { |
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//reset buffer code table |
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msf_put_code(&buf, &blockBits, codeBits, tableSize); |
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msf_lzw_reset(&lzw, tableSize, tableIdx); |
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} else { |
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(&lzw.data[lastCode * lzw.stride])[color] = lzw.len; |
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++lzw.len; |
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} |
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lastCode = color; |
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} else { |
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lastCode = code; |
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} |
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} |
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//write code for leftover index buffer contents, then the end code |
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|
MSF_GIF_FREE(allocContext, lzw.data, lzwAllocSize); |
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|
msf_put_code(&buf, &blockBits, msf_bit_log(lzw.len - 1), lastCode); |
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msf_put_code(&buf, &blockBits, msf_bit_log(lzw.len), tableSize + 1); |
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//flush remaining data |
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|
if (blockBits > 8) { |
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int bytes = (blockBits + 7) / 8; //round up |
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buf.head[0] = bytes - 1; |
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buf.head += bytes; |
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} |
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*buf.head++ = 0; //terminating block |
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|
return buf; |
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|
|
} |
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|
|
|
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// |
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|
/// Incremental API /// |
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|
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// |
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|
size_t msf_gif_begin(MsfGifState * handle, const char * outputFilePath, int width, int height) { MsfTimeFunc |
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|
//TODO: convert this to UTF-16 to correctly handle unicode on windows!?!? |
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|
|
// (or just say "do it yourself" now that replacing fopen is a thing?) |
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|
|
if (!(handle->fp = MSF_GIF_FOPEN(handle->customOutputContext, outputFilePath))) return 0; |
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|
|
MsfCookedFrame empty = {0}; //god I hate MSVC... |
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|
|
handle->previousFrame = empty; |
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|
|
handle->previousFrame.depth = 15; |
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|
|
handle->width = width; |
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|
|
handle->height = height; |
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|
|
handle->totalBytesWritten = 0; |
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|
|
|
|
|
|
//NOTE: because __attribute__((__packed__)) is annoyingly compiler-specific, we do this unreadable weirdness |
|
|
|
char headerBytes[33] = "GIF89a\0\0\0\0\x10\0\0" "\x21\xFF\x0BNETSCAPE2.0\x03\x01\0\0\0"; |
|
|
|
memcpy(&headerBytes[6], &width, 2); |
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|
|
memcpy(&headerBytes[8], &height, 2); |
|
|
|
if (!MSF_GIF_FWRITE(handle->customOutputContext, handle->fp, headerBytes, 32)) { |
|
|
|
MSF_GIF_FCLOSE(handle->customOutputContext, handle->fp); |
|
|
|
return 0; |
|
|
|
} |
|
|
|
handle->totalBytesWritten += 32; |
|
|
|
return handle->totalBytesWritten; |
|
|
|
} |
|
|
|
|
|
|
|
size_t msf_gif_frame(MsfGifState * handle, |
|
|
|
uint8_t * pixelData, int centiSecondsPerFame, int maxBitDepth, int pitchInBytes) |
|
|
|
{ MsfTimeFunc |
|
|
|
maxBitDepth = msf_imax(1, msf_imin(16, maxBitDepth)); |
|
|
|
if (pitchInBytes == 0) pitchInBytes = handle->width * 4; |
|
|
|
if (pitchInBytes < 0) pixelData -= pitchInBytes * (handle->height - 1); |
|
|
|
MsfCookedFrame frame = msf_cook_frame(handle->customAllocatorContext, handle->width, handle->height, pitchInBytes, |
|
|
|
// msf_imin(maxBitDepth, handle->previousFrame.depth + 1), pixelData); |
|
|
|
msf_imin(maxBitDepth, handle->previousFrame.depth + 160 / msf_imax(1, handle->previousFrame.count)), pixelData); |
|
|
|
if (!frame.pixels) { MSF_GIF_FCLOSE(handle->customOutputContext, handle->fp); return 0; } |
|
|
|
MsfFileBuffer buf = msf_compress_frame(handle->customAllocatorContext, |
|
|
|
handle->width, handle->height, centiSecondsPerFame, frame, handle->previousFrame); |
|
|
|
if (!buf.block) { MSF_GIF_FCLOSE(handle->customOutputContext, handle->fp); return 0; } |
|
|
|
if (!MSF_GIF_FWRITE(handle->customOutputContext, handle->fp, buf.block, buf.head - buf.block)) { |
|
|
|
MSF_GIF_FCLOSE(handle->customOutputContext, handle->fp); |
|
|
|
return 0; |
|
|
|
} |
|
|
|
handle->totalBytesWritten += buf.head - buf.block; |
|
|
|
MSF_GIF_FREE(handle->customAllocatorContext, buf.block, buf.end - buf.block); |
|
|
|
MSF_GIF_FREE(handle->customAllocatorContext, frame.used, msfUsedAllocSize); |
|
|
|
MSF_GIF_FREE(handle->customAllocatorContext, |
|
|
|
handle->previousFrame.pixels, handle->width * handle->height * sizeof(uint32_t)); |
|
|
|
handle->previousFrame = frame; |
|
|
|
return handle->totalBytesWritten; |
|
|
|
} |
|
|
|
|
|
|
|
size_t msf_gif_end(MsfGifState * handle) { MsfTimeFunc |
|
|
|
int allocSize = handle->width * handle->height * sizeof(uint32_t); |
|
|
|
uint8_t trailingMarker = 0x3B; |
|
|
|
if (!MSF_GIF_FWRITE(handle->customOutputContext, handle->fp, &trailingMarker, 1)) { |
|
|
|
MSF_GIF_FCLOSE(handle->customOutputContext, handle->fp); |
|
|
|
MSF_GIF_FREE(handle->customAllocatorContext, handle->previousFrame.pixels, allocSize); |
|
|
|
return 0; |
|
|
|
} |
|
|
|
handle->totalBytesWritten += 1; |
|
|
|
if (MSF_GIF_FCLOSE(handle->customOutputContext, handle->fp)) return 0; |
|
|
|
MSF_GIF_FREE(handle->customAllocatorContext, handle->previousFrame.pixels, allocSize); |
|
|
|
return handle->totalBytesWritten; |
|
|
|
} |
|
|
|
|
|
|
|
#endif //MSF_GIF_ALREADY_IMPLEMENTED_IN_THIS_TRANSLATION_UNIT |
|
|
|
#endif //MSF_GIF_IMPL |
|
|
|
|
|
|
|
/* |
|
|
|
------------------------------------------------------------------------------ |
|
|
|
This software is available under 2 licenses -- choose whichever you prefer. |
|
|
|
------------------------------------------------------------------------------ |
|
|
|
ALTERNATIVE A - MIT License |
|
|
|
Copyright (c) 2020 Miles Fogle |
|
|
|
Permission is hereby granted, free of charge, to any person obtaining a copy of |
|
|
|
this software and associated documentation files (the "Software"), to deal in |
|
|
|
the Software without restriction, including without limitation the rights to |
|
|
|
use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies |
|
|
|
of the Software, and to permit persons to whom the Software is furnished to do |
|
|
|
so, subject to the following conditions: |
|
|
|
The above copyright notice and this permission notice shall be included in all |
|
|
|
copies or substantial portions of the Software. |
|
|
|
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
|
|
|
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
|
|
|
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
|
|
|
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
|
|
|
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
|
|
|
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE |
|
|
|
SOFTWARE. |
|
|
|
------------------------------------------------------------------------------ |
|
|
|
ALTERNATIVE B - Public Domain (www.unlicense.org) |
|
|
|
This is free and unencumbered software released into the public domain. |
|
|
|
Anyone is free to copy, modify, publish, use, compile, sell, or distribute this |
|
|
|
software, either in source code form or as a compiled binary, for any purpose, |
|
|
|
commercial or non-commercial, and by any means. |
|
|
|
In jurisdictions that recognize copyright laws, the author or authors of this |
|
|
|
software dedicate any and all copyright interest in the software to the public |
|
|
|
domain. We make this dedication for the benefit of the public at large and to |
|
|
|
the detriment of our heirs and successors. We intend this dedication to be an |
|
|
|
overt act of relinquishment in perpetuity of all present and future rights to |
|
|
|
this software under copyright law. |
|
|
|
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
|
|
|
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
|
|
|
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
|
|
|
AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN |
|
|
|
ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION |
|
|
|
WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. |
|
|
|
------------------------------------------------------------------------------ |
|
|
|
*/ |