69 lines
1.1 KiB
C
69 lines
1.1 KiB
C
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/*
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* blkinit.c
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*
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* Block outputting initialisation
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*/
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#include "encoder.h"
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/*
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* Create lookup table for MP_SLOT() macro
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*/
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void create_slot_lookup_table(t_encoder_context *context)
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{
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int j;
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int p;
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int elements_to_init;
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ushort slotnum;
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context->enc_slot_table[0] = 0;
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context->enc_slot_table[1] = 1;
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context->enc_slot_table[2] = 2;
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context->enc_slot_table[3] = 3;
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elements_to_init = 2;
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slotnum = 4;
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p = 4;
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do
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{
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for (j = elements_to_init; j > 0; j--)
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context->enc_slot_table[p++] = slotnum;
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slotnum++;
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for (j = elements_to_init; j > 0; j--)
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context->enc_slot_table[p++] = slotnum;
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slotnum++;
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elements_to_init <<= 1;
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} while (p < 1024);
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}
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/*
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* Create lookup table for figuring out how many
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* ones there are in a given byte.
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*/
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void create_ones_table(t_encoder_context *context)
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{
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int i, j;
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byte ones;
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for (i = 0; i < 256; i++)
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{
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ones = 0;
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for (j = i; j; j >>= 1)
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{
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if (j & 1)
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ones++;
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}
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context->enc_ones[i] = ones;
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}
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}
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