forked from len0rd/rockbox
b8238f7b20
Added jpeg decoder jpegp.c using RAINBOW lib. Currently enabled only for pictures not supported by old decoder (as old decoder more optimized for low mem targets) Someone TODO: * Old decoder has optimized downscale logic which new decoder doesn't have (it gives big difference in required memory and time for decoding). This logic should be ported/adapted if possible. * Add smooth downscaling. * Grayscale support Change-Id: Ie96bc62848b51cc6a3942f8e069ec6ab02dc1c56
56 lines
2.2 KiB
C
56 lines
2.2 KiB
C
/*
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"GETC" Interface for byte input (i.e. started as a wrapper for getc())
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For image- and video decoders I needed a transparent mechanism for
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opening and reading the input data:
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- either from streams (eg. coded video)
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- or preloaded into memory (eg. small GIF/PNG images)
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RAINBOW is only dependent on the GETC Interface for byte input.
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File stream input is used during development and testing (FILEGETC.C).
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In the OS image Rainbow can be linked with MEMGETC.C for memory input.
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No other changes necessary in RAINBOW.
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* Copyright (c) 2017 A. Tarpai
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in all
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* copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
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* SOFTWARE.
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*/
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// For decoders
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extern int GETC(void);
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// Multibyte helpers
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extern int GETWbi(void); // read word (16-bit) big-endian
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extern int GETWli(void); // little-endian
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extern int GETDbi(void); // read double word (32-bit) big-endian
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extern int GETDli(void); // little-endian
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// positioning
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extern void SEEK(int); // move relative to current
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extern void POS(int); // move absolute position (TIFF)
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extern int TELL(void); // read actual position
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// For RAINBOW clients to implement outside of Rainbow Library
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extern void *OPEN(char*);
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extern void CLOSE(void);
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