X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=bitstream.h;h=5d6be3be2693a84f8107504f4a086dfa578c817b;hp=0c0a1eba609629ed488746906443bb9ed34fabbc;hb=656a02453498156bab09763011ff43b81db57634;hpb=7978ce515fc2c19ffd8fd7d8fe356f5fa628d7ff;ds=sidebyside

diff --git a/bitstream.h b/bitstream.h
index 0c0a1eba..5d6be3be 100644
--- a/bitstream.h
+++ b/bitstream.h
@@ -21,10 +21,16 @@ struct getbit_context {
 
 #define VLC_TYPE int16_t
 
+/** A variable length code table. */
 struct vlc {
+	/** Number of bits of the table. */
 	int bits;
-	VLC_TYPE(*table)[2];	///< code, bits
-	int table_size, table_allocated;
+	/** The code and the bits table. */
+	VLC_TYPE(*table)[2];
+	/** The size of the table. */
+	int table_size;
+	/** Amount of memory allocated so far. */
+	int table_allocated;
 };
 
 static inline uint32_t show_bits(struct getbit_context *gbc, int num)
@@ -53,7 +59,7 @@ static inline unsigned int get_bits(struct getbit_context *gbc, int n)
 }
 
 /* This is rather hot, we can do better than get_bits(gbc, 1). */
-static inline unsigned int get_bits1(struct getbit_context *gbc)
+static inline unsigned int get_bit(struct getbit_context *gbc)
 {
 	int idx = gbc->index++;
 	uint8_t tmp = gbc->buffer[idx >> 3], mask = (1 << (7 - (idx & 7)));
@@ -63,9 +69,9 @@ static inline unsigned int get_bits1(struct getbit_context *gbc)
 /**
  * Initialize a getbit_context structure.
  *
- * \param buffer The bitstream buffer. It must be FF_INPUT_BUFFER_PADDING_SIZE
- * bytes larger then the actual read bits * because some optimized bitstream
- * readers read 32 or 64 bit at once and could read over the end.
+ * \param buffer The bitstream buffer. It must be 4 bytes larger then the
+ * actual read bits because the bitstream reader might read 32 bits at once and
+ * could read over the end.
  *
  * \param bit_size The size of the buffer in bytes.
  */
@@ -79,40 +85,7 @@ static inline void init_get_bits(struct getbit_context *gbc,
 
 void init_vlc(struct vlc *vlc, int nb_bits, int nb_codes, const void *bits,
 		const void *codes, int codes_size);
-
 void free_vlc(struct vlc *vlc);
+int get_vlc(struct getbit_context *gbc, VLC_TYPE(*table)[2], int bits,
+		int max_depth);
 
-/**
- * Parse a vlc code.
- *
- * \param bits The number of bits which will be read at once, must be
- * identical to nb_bits in init_vlc()
- *
- * \param max_depth The number of times bits bits must be read to completely
- * read the longest vlc code = (max_vlc_length + bits - 1) / bits.
- */
-static inline int get_vlc(struct getbit_context *gbc, VLC_TYPE(*table)[2],
-		int bits, int max_depth)
-{
-	int n, idx, nb_bits, code;
-
-	idx = show_bits(gbc, bits);
-	code = table[idx][0];
-	n = table[idx][1];
-	if (max_depth > 1 && n < 0) {
-		skip_bits(gbc, bits);
-		nb_bits = -n;
-		idx = show_bits(gbc, nb_bits) + code;
-		code = table[idx][0];
-		n = table[idx][1];
-		if (max_depth > 2 && n < 0) {
-			skip_bits(gbc, nb_bits);
-			nb_bits = -n;
-			idx = show_bits(gbc, nb_bits) + code;
-			code = table[idx][0];
-			n = table[idx][1];
-		}
-	}
-	skip_bits(gbc, n);
-	return code;
-}