• Paul Wilkins's avatar
    Minor rate control refactoring and experiments. · 97da8b8c
    Paul Wilkins authored
    Some minor refactoring code relating to estimates of
    bits per MB at a given Q and estimating the allowed Q range.
    
    Most of the changes here were included in a previous commit.
    This commit seeks to separate out the refactoring from more
    the material changes.
    
    Two #define control flags have been added for experimentation.
    
    ONE_SHOT_Q_ESTIMATE force the two pass encoder to
    use its initial Q range estimate for the whole clip even if this results
    in a miss on the target data rate. In effect this tightens the Q range
    seen at the expense of rate control accuracy.
    
    DISABLE_RC_LONG_TERM_MEM is a related flag that disables the
    long term memory in the rate control. Local adjustments are still
    made to try and better hit the rate target on a per frame basis but
    the impact of rate control misses is not propagated to the remainder
    of the clip. This means that for example an overshoot early on will not
    cause frames later in the clip to be starved of bits. Again the result
    of this relaxation amy be less rate control accuracy especially on short
    clips.
    
    The flags are disabled by default for now.
    
    Change-Id: I7482f980146d8ea033b5d50cc689f772e4bd119e
    97da8b8c
md5_utils.h 1.42 KiB
/*
 * This is the header file for the MD5 message-digest algorithm.
 * The algorithm is due to Ron Rivest.  This code was
 * written by Colin Plumb in 1993, no copyright is claimed.
 * This code is in the public domain; do with it what you wish.
 * Equivalent code is available from RSA Data Security, Inc.
 * This code has been tested against that, and is equivalent,
 * except that you don't need to include two pages of legalese
 * with every copy.
 * To compute the message digest of a chunk of bytes, declare an
 * MD5Context structure, pass it to MD5Init, call MD5Update as
 * needed on buffers full of bytes, and then call MD5Final, which
 * will fill a supplied 16-byte array with the digest.
 * Changed so as no longer to depend on Colin Plumb's `usual.h'
 * header definitions
 *  - Ian Jackson <ian@chiark.greenend.org.uk>.
 * Still in the public domain.
#ifndef MD5_UTILS_H_
#define MD5_UTILS_H_
#ifdef __cplusplus
extern "C" {
#endif
#define md5byte unsigned char
#define UWORD32 unsigned int
typedef struct MD5Context MD5Context;
struct MD5Context {
  UWORD32 buf[4];
  UWORD32 bytes[2];
  UWORD32 in[16];
void MD5Init(struct MD5Context *context);
void MD5Update(struct MD5Context *context, md5byte const *buf, unsigned len);
void MD5Final(unsigned char digest[16], struct MD5Context *context);
void MD5Transform(UWORD32 buf[4], UWORD32 const in[16]);
#ifdef __cplusplus
}  // extern "C"
#endif
#endif  // MD5_UTILS_H_