mirror of
https://github.com/pineappleEA/pineapple-src.git
synced 2024-12-05 00:28:25 -05:00
201 lines
7.9 KiB
C
Executable File
201 lines
7.9 KiB
C
Executable File
/*
|
|
* Copyright (c) 2016 Umair Khan <omerjerk@gmail.com>
|
|
*
|
|
* This file is part of FFmpeg.
|
|
*
|
|
* FFmpeg is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Lesser General Public
|
|
* License as published by the Free Software Foundation; either
|
|
* version 2.1 of the License, or (at your option) any later version.
|
|
*
|
|
* FFmpeg is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
* Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public
|
|
* License along with FFmpeg; if not, write to the Free Software
|
|
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
|
|
*/
|
|
|
|
#include "mlz.h"
|
|
|
|
av_cold void ff_mlz_init_dict(void* context, MLZ *mlz) {
|
|
mlz->dict = av_mallocz_array(TABLE_SIZE, sizeof(*mlz->dict));
|
|
|
|
mlz->flush_code = FLUSH_CODE;
|
|
mlz->current_dic_index_max = DIC_INDEX_INIT;
|
|
mlz->dic_code_bit = CODE_BIT_INIT;
|
|
mlz->bump_code = (DIC_INDEX_INIT - 1);
|
|
mlz->next_code = FIRST_CODE;
|
|
mlz->freeze_flag = 0;
|
|
mlz->context = context;
|
|
}
|
|
|
|
av_cold void ff_mlz_flush_dict(MLZ *mlz) {
|
|
MLZDict *dict = mlz->dict;
|
|
int i;
|
|
for ( i = 0; i < TABLE_SIZE; i++ ) {
|
|
dict[i].string_code = CODE_UNSET;
|
|
dict[i].parent_code = CODE_UNSET;
|
|
dict[i].match_len = 0;
|
|
}
|
|
mlz->current_dic_index_max = DIC_INDEX_INIT;
|
|
mlz->dic_code_bit = CODE_BIT_INIT; // DicCodeBitInit;
|
|
mlz->bump_code = mlz->current_dic_index_max - 1;
|
|
mlz->next_code = FIRST_CODE;
|
|
mlz->freeze_flag = 0;
|
|
}
|
|
|
|
static void set_new_entry_dict(MLZDict* dict, int string_code, int parent_code, int char_code) {
|
|
dict[string_code].parent_code = parent_code;
|
|
dict[string_code].string_code = string_code;
|
|
dict[string_code].char_code = char_code;
|
|
if (parent_code < FIRST_CODE) {
|
|
dict[string_code].match_len = 2;
|
|
} else {
|
|
dict[string_code].match_len = (dict[parent_code].match_len) + 1;
|
|
}
|
|
}
|
|
|
|
static int decode_string(MLZ* mlz, unsigned char *buff, int string_code, int *first_char_code, unsigned long bufsize) {
|
|
MLZDict* dict = mlz->dict;
|
|
unsigned long count, offset;
|
|
int current_code, parent_code, tmp_code;
|
|
|
|
count = 0;
|
|
current_code = string_code;
|
|
*first_char_code = CODE_UNSET;
|
|
|
|
while (count < bufsize) {
|
|
switch (current_code) {
|
|
case CODE_UNSET:
|
|
return count;
|
|
break;
|
|
default:
|
|
if (current_code < FIRST_CODE) {
|
|
*first_char_code = current_code;
|
|
buff[0] = current_code;
|
|
count++;
|
|
return count;
|
|
} else {
|
|
offset = dict[current_code].match_len - 1;
|
|
tmp_code = dict[current_code].char_code;
|
|
if (offset >= bufsize) {
|
|
av_log(mlz->context, AV_LOG_ERROR, "MLZ offset error.\n");
|
|
return count;
|
|
}
|
|
buff[offset] = tmp_code;
|
|
count++;
|
|
}
|
|
current_code = dict[current_code].parent_code;
|
|
if ((current_code < 0) || (current_code > (DIC_INDEX_MAX - 1))) {
|
|
av_log(mlz->context, AV_LOG_ERROR, "MLZ dic index error.\n");
|
|
return count;
|
|
}
|
|
if (current_code > FIRST_CODE) {
|
|
parent_code = dict[current_code].parent_code;
|
|
offset = (dict[current_code].match_len) - 1;
|
|
if (parent_code < 0 || parent_code > DIC_INDEX_MAX-1) {
|
|
av_log(mlz->context, AV_LOG_ERROR, "MLZ dic index error.\n");
|
|
return count;
|
|
}
|
|
if (( offset > (DIC_INDEX_MAX - 1))) {
|
|
av_log(mlz->context, AV_LOG_ERROR, "MLZ dic offset error.\n");
|
|
return count;
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
return count;
|
|
}
|
|
|
|
static int input_code(GetBitContext* gb, int len) {
|
|
int tmp_code = 0;
|
|
int i;
|
|
for (i = 0; i < len; ++i) {
|
|
tmp_code |= get_bits1(gb) << i;
|
|
}
|
|
return tmp_code;
|
|
}
|
|
|
|
int ff_mlz_decompression(MLZ* mlz, GetBitContext* gb, int size, unsigned char *buff) {
|
|
MLZDict *dict = mlz->dict;
|
|
unsigned long output_chars;
|
|
int string_code, last_string_code, char_code;
|
|
|
|
string_code = 0;
|
|
char_code = -1;
|
|
last_string_code = -1;
|
|
output_chars = 0;
|
|
|
|
while (output_chars < size) {
|
|
string_code = input_code(gb, mlz->dic_code_bit);
|
|
switch (string_code) {
|
|
case FLUSH_CODE:
|
|
case MAX_CODE:
|
|
ff_mlz_flush_dict(mlz);
|
|
char_code = -1;
|
|
last_string_code = -1;
|
|
break;
|
|
case FREEZE_CODE:
|
|
mlz->freeze_flag = 1;
|
|
break;
|
|
default:
|
|
if (string_code > mlz->current_dic_index_max) {
|
|
av_log(mlz->context, AV_LOG_ERROR, "String code %d exceeds maximum value of %d.\n", string_code, mlz->current_dic_index_max);
|
|
return output_chars;
|
|
}
|
|
if (string_code == (int) mlz->bump_code) {
|
|
++mlz->dic_code_bit;
|
|
mlz->current_dic_index_max *= 2;
|
|
mlz->bump_code = mlz->current_dic_index_max - 1;
|
|
} else {
|
|
if (string_code >= mlz->next_code) {
|
|
int ret = decode_string(mlz, &buff[output_chars], last_string_code, &char_code, size - output_chars);
|
|
if (ret < 0 || ret > size - output_chars) {
|
|
av_log(mlz->context, AV_LOG_ERROR, "output chars overflow\n");
|
|
return output_chars;
|
|
}
|
|
output_chars += ret;
|
|
ret = decode_string(mlz, &buff[output_chars], char_code, &char_code, size - output_chars);
|
|
if (ret < 0 || ret > size - output_chars) {
|
|
av_log(mlz->context, AV_LOG_ERROR, "output chars overflow\n");
|
|
return output_chars;
|
|
}
|
|
output_chars += ret;
|
|
set_new_entry_dict(dict, mlz->next_code, last_string_code, char_code);
|
|
if (mlz->next_code >= TABLE_SIZE - 1) {
|
|
av_log(mlz->context, AV_LOG_ERROR, "Too many MLZ codes\n");
|
|
return output_chars;
|
|
}
|
|
mlz->next_code++;
|
|
} else {
|
|
int ret = decode_string(mlz, &buff[output_chars], string_code, &char_code, size - output_chars);
|
|
if (ret < 0 || ret > size - output_chars) {
|
|
av_log(mlz->context, AV_LOG_ERROR, "output chars overflow\n");
|
|
return output_chars;
|
|
}
|
|
output_chars += ret;
|
|
if (output_chars <= size && !mlz->freeze_flag) {
|
|
if (last_string_code != -1) {
|
|
set_new_entry_dict(dict, mlz->next_code, last_string_code, char_code);
|
|
if (mlz->next_code >= TABLE_SIZE - 1) {
|
|
av_log(mlz->context, AV_LOG_ERROR, "Too many MLZ codes\n");
|
|
return output_chars;
|
|
}
|
|
mlz->next_code++;
|
|
}
|
|
} else {
|
|
break;
|
|
}
|
|
}
|
|
last_string_code = string_code;
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
return output_chars;
|
|
}
|