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-rw-r--r--src/main/jni/giflib/gif_hash.h39
1 files changed, 39 insertions, 0 deletions
diff --git a/src/main/jni/giflib/gif_hash.h b/src/main/jni/giflib/gif_hash.h
new file mode 100644
index 000000000..ac20a43cb
--- /dev/null
+++ b/src/main/jni/giflib/gif_hash.h
@@ -0,0 +1,39 @@
+/******************************************************************************
+
+gif_hash.h - magfic constants and declarations for GIF LZW
+
+******************************************************************************/
+
+#ifndef _GIF_HASH_H_
+#define _GIF_HASH_H_
+
+#include <unistd.h>
+#include <stdint.h>
+
+#define HT_SIZE 8192 /* 12bits = 4096 or twice as big! */
+#define HT_KEY_MASK 0x1FFF /* 13bits keys */
+#define HT_KEY_NUM_BITS 13 /* 13bits keys */
+#define HT_MAX_KEY 8191 /* 13bits - 1, maximal code possible */
+#define HT_MAX_CODE 4095 /* Biggest code possible in 12 bits. */
+
+/* The 32 bits of the long are divided into two parts for the key & code: */
+/* 1. The code is 12 bits as our compression algorithm is limited to 12bits */
+/* 2. The key is 12 bits Prefix code + 8 bit new char or 20 bits. */
+/* The key is the upper 20 bits. The code is the lower 12. */
+#define HT_GET_KEY(l) (l >> 12)
+#define HT_GET_CODE(l) (l & 0x0FFF)
+#define HT_PUT_KEY(l) (l << 12)
+#define HT_PUT_CODE(l) (l & 0x0FFF)
+
+typedef struct GifHashTableType {
+ uint32_t HTable[HT_SIZE];
+} GifHashTableType;
+
+GifHashTableType *_InitHashTable(void);
+void _ClearHashTable(GifHashTableType *HashTable);
+void _InsertHashTable(GifHashTableType *HashTable, uint32_t Key, int Code);
+int _ExistsHashTable(GifHashTableType *HashTable, uint32_t Key);
+
+#endif /* _GIF_HASH_H_ */
+
+/* end */