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The Independent JPEG Group's JPEG software v4a

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This commit is contained in:
Thomas G. Lane
1993-02-18 00:00:00 +00:00
committed by DRC
parent 88aeed428f
commit cc7150e281
42 changed files with 1083 additions and 451 deletions
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19
jchuff.c
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@@ -1,7 +1,7 @@
/*
* jchuff.c
*
* Copyright (C) 1991, 1992, Thomas G. Lane.
* Copyright (C) 1991, 1992, 1993, Thomas G. Lane.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
@@ -66,15 +66,12 @@ fix_huff_tbl (HUFF_TBL * htbl)
/* Set any codeless symbols to have code length 0;
* this allows emit_bits to detect any attempt to emit such symbols.
*/
MEMZERO(htbl->ehufsi, SIZEOF(htbl->ehufsi));
MEMZERO(htbl->priv.enc.ehufsi, SIZEOF(htbl->priv.enc.ehufsi));
for (p = 0; p < lastp; p++) {
htbl->ehufco[htbl->huffval[p]] = huffcode[p];
htbl->ehufsi[htbl->huffval[p]] = huffsize[p];
htbl->priv.enc.ehufco[htbl->huffval[p]] = huffcode[p];
htbl->priv.enc.ehufsi[htbl->huffval[p]] = huffsize[p];
}
/* We don't bother to fill in the decoding tables mincode[], maxcode[], */
/* and valptr[], since they are not used for encoding. */
}
@@ -179,7 +176,7 @@ encode_one_block (JBLOCK block, HUFF_TBL *dctbl, HUFF_TBL *actbl)
}
/* Emit the Huffman-coded symbol for the number of bits */
emit_bits(dctbl->ehufco[nbits], dctbl->ehufsi[nbits]);
emit_bits(dctbl->priv.enc.ehufco[nbits], dctbl->priv.enc.ehufsi[nbits]);
/* Emit that number of bits of the value, if positive, */
/* or the complement of its magnitude, if negative. */
@@ -196,7 +193,7 @@ encode_one_block (JBLOCK block, HUFF_TBL *dctbl, HUFF_TBL *actbl)
} else {
/* if run length > 15, must emit special run-length-16 codes (0xF0) */
while (r > 15) {
emit_bits(actbl->ehufco[0xF0], actbl->ehufsi[0xF0]);
emit_bits(actbl->priv.enc.ehufco[0xF0], actbl->priv.enc.ehufsi[0xF0]);
r -= 16;
}
@@ -214,7 +211,7 @@ encode_one_block (JBLOCK block, HUFF_TBL *dctbl, HUFF_TBL *actbl)
/* Emit Huffman symbol for run length / number of bits */
i = (r << 4) + nbits;
emit_bits(actbl->ehufco[i], actbl->ehufsi[i]);
emit_bits(actbl->priv.enc.ehufco[i], actbl->priv.enc.ehufsi[i]);
/* Emit that number of bits of the value, if positive, */
/* or the complement of its magnitude, if negative. */
@@ -226,7 +223,7 @@ encode_one_block (JBLOCK block, HUFF_TBL *dctbl, HUFF_TBL *actbl)
/* If the last coef(s) were zero, emit an end-of-block code */
if (r > 0)
emit_bits(actbl->ehufco[0], actbl->ehufsi[0]);
emit_bits(actbl->priv.enc.ehufco[0], actbl->priv.enc.ehufsi[0]);
}