denuvo-ref/precomp-cpp
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Improve JPG parsing

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- fixes JPG part of #52
- improves JPG parsing speed (issue #5)
This commit is contained in:
Christian Schneider 2017-03-12 11:00:38 +01:00
parent 7d4ab6554c
commit f86c9b420e
1 changed files with 20 additions and 1 deletions
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21
precomp.cpp
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@ -252,6 +252,7 @@ unsigned int* idat_lengths = NULL;
unsigned int* idat_crcs = NULL;
int idat_count;
long long suppress_jpg_parsing_until;
long long suppress_mp3_type_until[16];
long long suppress_mp3_big_value_pairs_sum;
long long mp3_parsing_cache_second_frame;
@ -505,6 +506,9 @@ int init(int argc, char* argv[]) {
use_zlib_level[i] = true;
}
// init JPG suppression
suppress_jpg_parsing_until = -1;
// init MP3 suppression
for (i = 0; i < 16; i++) {
suppress_mp3_type_until[i] = -1;
@ -3713,7 +3717,7 @@ bool compress_file(float min_percent, float max_percent) {
}
}
if ((!compressed_data_found) && (use_jpg)) { // no GIF header -> JPG header?
if ((!compressed_data_found) && (use_jpg) && (input_file_pos > suppress_jpg_parsing_until)) { // no GIF header -> JPG header?
if ((in_buf[cb] == 0xFF) && (in_buf[cb + 1] == 0xD8)) { // SOI (FF D8)
if ((in_buf[cb + 2] == 0xFF)) {
saved_input_file_pos = input_file_pos;
@ -3792,6 +3796,16 @@ bool compress_file(float min_percent, float max_percent) {
input_file_pos = saved_input_file_pos;
cb = saved_cb;
}
} else if (eoi_count >= 256) {
// more than 255 nested images -> seems to be other data
// skip until eoi_count is guaranteed to be under 16 to speed
// up the parsing
suppress_jpg_parsing_until = saved_input_file_pos + (eoi_count - 16) * 2;
if (DEBUG_MODE) {
printf("Ignoring following JPG streams until position ");
print64(suppress_jpg_parsing_until);
printf(" to avoid slowdown\n");
}
}
}
}
@ -8814,6 +8828,7 @@ void recursion_push() {
recursion_stack_push(&global_min_percent, sizeof(global_min_percent));
recursion_stack_push(&global_max_percent, sizeof(global_max_percent));
recursion_stack_push(&comp_decomp_state, sizeof(comp_decomp_state));
recursion_stack_push(&suppress_jpg_parsing_until, sizeof(suppress_jpg_parsing_until));
recursion_stack_push(&suppress_mp3_type_until[0], sizeof(suppress_mp3_type_until[0]) * 16);
recursion_stack_push(&suppress_mp3_big_value_pairs_sum, sizeof(suppress_mp3_big_value_pairs_sum));
recursion_stack_push(&mp3_parsing_cache_second_frame, sizeof(mp3_parsing_cache_second_frame));
@ -8833,6 +8848,7 @@ void recursion_pop() {
recursion_stack_pop(&mp3_parsing_cache_second_frame, sizeof(mp3_parsing_cache_second_frame));
recursion_stack_pop(&suppress_mp3_big_value_pairs_sum, sizeof(suppress_mp3_big_value_pairs_sum));
recursion_stack_pop(&suppress_mp3_type_until[0], sizeof(suppress_mp3_type_until[0]) * 16);
recursion_stack_pop(&suppress_jpg_parsing_until, sizeof(suppress_jpg_parsing_until));
recursion_stack_pop(&comp_decomp_state, sizeof(comp_decomp_state));
recursion_stack_pop(&global_max_percent, sizeof(global_max_percent));
recursion_stack_pop(&global_min_percent, sizeof(global_min_percent));
@ -8929,6 +8945,9 @@ recursion_result recursion_compress(int compressed_bytes, int decompressed_bytes
local_penalty_bytes = new char[MAX_PENALTY_BYTES];
best_penalty_bytes = new char[MAX_PENALTY_BYTES];
// init JPG suppression
suppress_jpg_parsing_until = -1;
// init MP3 suppression
for (int i = 0; i < 16; i++) {
suppress_mp3_type_until[i] = -1;