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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 00:47:55 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 00:47:55 +0000 |
commit | 26a029d407be480d791972afb5975cf62c9360a6 (patch) | |
tree | f435a8308119effd964b339f76abb83a57c29483 /media/libjpeg/jchuff.h | |
parent | Initial commit. (diff) | |
download | firefox-26a029d407be480d791972afb5975cf62c9360a6.tar.xz firefox-26a029d407be480d791972afb5975cf62c9360a6.zip |
Adding upstream version 124.0.1.upstream/124.0.1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | media/libjpeg/jchuff.h | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/media/libjpeg/jchuff.h b/media/libjpeg/jchuff.h new file mode 100644 index 0000000000..da7809a94b --- /dev/null +++ b/media/libjpeg/jchuff.h @@ -0,0 +1,50 @@ +/* + * jchuff.h + * + * This file was part of the Independent JPEG Group's software: + * Copyright (C) 1991-1997, Thomas G. Lane. + * libjpeg-turbo Modifications: + * Copyright (C) 2022, D. R. Commander. + * For conditions of distribution and use, see the accompanying README.ijg + * file. + * + * This file contains declarations for Huffman entropy encoding routines + * that are shared between the sequential encoder (jchuff.c) and the + * progressive encoder (jcphuff.c). No other modules need to see these. + */ + +/* The legal range of a DCT coefficient is + * -1024 .. +1023 for 8-bit data; + * -16384 .. +16383 for 12-bit data. + * Hence the magnitude should always fit in 10 or 14 bits respectively. + */ + +#if BITS_IN_JSAMPLE == 8 +#define MAX_COEF_BITS 10 +#else +#define MAX_COEF_BITS 14 +#endif + +/* The progressive Huffman encoder uses an unsigned 16-bit data type to store + * absolute values of coefficients, because it is possible to inject a + * coefficient value of -32768 into the encoder by attempting to transform a + * malformed 12-bit JPEG image, and the absolute value of -32768 would overflow + * a signed 16-bit integer. + */ +typedef unsigned short UJCOEF; + +/* Derived data constructed for each Huffman table */ + +typedef struct { + unsigned int ehufco[256]; /* code for each symbol */ + char ehufsi[256]; /* length of code for each symbol */ + /* If no code has been allocated for a symbol S, ehufsi[S] contains 0 */ +} c_derived_tbl; + +/* Expand a Huffman table definition into the derived format */ +EXTERN(void) jpeg_make_c_derived_tbl(j_compress_ptr cinfo, boolean isDC, + int tblno, c_derived_tbl **pdtbl); + +/* Generate an optimal table definition given the specified counts */ +EXTERN(void) jpeg_gen_optimal_table(j_compress_ptr cinfo, JHUFF_TBL *htbl, + long freq[]); |