/** Structure for bistream I/O. */
struct getbit_context {
- /* Start of the internal buffer. */
+ /** Start of the internal buffer. */
const uint8_t *buffer;
- /* End of the internal buffer. */
+ /** End of the internal buffer. */
const uint8_t *buffer_end;
/** Bit counter. */
int index;
#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)
{
int idx = gbc->index;
const uint8_t *p = gbc->buffer + (idx >> 3);
- uint32_t x = ((p[0] << 24) | (p[1] << 16) | (p[2] << 8) | p[3]);
+ uint32_t x = (p[0] << 24) | (p[1] << 16) | (p[2] << 8) | p[3];
return (x << (idx & 7)) >> (32 - num);
}
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)));
+ uint8_t tmp = gbc->buffer[idx >> 3], mask = 1 << (7 - (idx & 7));
return !!(tmp & mask);
}
/**
* Initialize a getbit_context structure.
*
- * \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 gbc The structure to initialize.
+ * \param buffer The bitstream buffer.
+ * \param size The size of the buffer in bytes.
*
- * \param bit_size The size of the buffer in bytes.
+ * The bitstream buffer 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.
*/
static inline void init_get_bits(struct getbit_context *gbc,
const uint8_t *buffer, int size)
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);
-
+int get_vlc(struct getbit_context *gbc, VLC_TYPE(*table)[2], int bits);