codec.h

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/********************************************************************
 *                                                                  *
 * THIS FILE IS PART OF THE OggTheora SOFTWARE CODEC SOURCE CODE.   *
 * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS     *
 * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
 * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING.       *
 *                                                                  *
 * THE Theora SOURCE CODE IS COPYRIGHT (C) 2002-2007                *
 * by the Xiph.Org Foundation http://www.xiph.org/                  *
 *                                                                  *
 ********************************************************************

  function:
  last mod: $Id: theora.h,v 1.8 2004/03/15 22:17:32 derf Exp $

 ********************************************************************/

#if !defined(_O_THEORA_CODEC_H_)
# define _O_THEORA_CODEC_H_ (1)
# include <ogg/ogg.h>

#if defined(__cplusplus)
extern "C" {
#endif



#define TH_EFAULT     (-1)

#define TH_EINVAL     (-10)

#define TH_EBADHEADER (-20)

#define TH_ENOTFORMAT (-21)

#define TH_EVERSION   (-22)

#define TH_EIMPL      (-23)

#define TH_EBADPACKET (-24)

#define TH_DUPFRAME   (1)

typedef enum{
  TH_CS_UNSPECIFIED,
  TH_CS_ITU_REC_470M,
  TH_CS_ITU_REC_470BG,
  TH_CS_NSPACES
}th_colorspace;

typedef enum{
  TH_PF_420,
  TH_PF_RSVD,
  TH_PF_422,
  TH_PF_444,
  TH_PF_NFORMATS
}th_pixel_fmt;



typedef struct{
  int            width;
  int            height;
  int            stride;
  unsigned char *data;
}th_img_plane;

typedef th_img_plane th_ycbcr_buffer[3];

typedef struct{
  unsigned char version_major;
  unsigned char version_minor;
  unsigned char version_subminor;
  ogg_uint32_t  frame_width;
  ogg_uint32_t  frame_height;
  ogg_uint32_t  pic_width;
  ogg_uint32_t  pic_height;
  ogg_uint32_t  pic_x;
  ogg_uint32_t  pic_y;
  ogg_uint32_t  fps_numerator;
  ogg_uint32_t  fps_denominator;
  ogg_uint32_t  aspect_numerator;
  ogg_uint32_t  aspect_denominator;
  th_colorspace colorspace;
  th_pixel_fmt  pixel_fmt;
  /*TODO: Current encoder does not support CBR mode, or anything like it.
    We also don't really know what nominal rate each quality level
     corresponds to yet.*/
  int           target_bitrate;
  /*Currently this is set so that a qi of 0 corresponds to distortions of 24
     times the JND, and each increase by 16 halves that value.
    This gives us fine discrimination at low qualities, yet effective rate
     control at high qualities.
    The qi value 63 is special, however.
    For this, the highest quality, we use one half of a JND for our threshold.
    Due to the lower bounds placed on allowable quantizers in Theora, we will
     not actually be able to achieve quality this good, but this should
     provide as close to visually lossless quality as Theora is capable of.
    We could lift the quantizer restrictions without breaking VP3.1
     compatibility, but this would result in quantized coefficients that are
     too large for the current bitstream to be able to store.
    We'd have to redesign the token syntax to store these large coefficients,
     which would make transcoding complex.*/
  int           quality;
  int           keyframe_granule_shift;
}th_info;

typedef struct th_comment{
  char **user_comments;
  int   *comment_lengths;
  int    comments;
  char  *vendor;
}th_comment;



typedef unsigned char th_quant_base[64];

typedef struct{
  int                  nranges;
  const int           *sizes;
  const th_quant_base *base_matrices;
}th_quant_ranges;

typedef struct{
  ogg_uint16_t    dc_scale[64];
  ogg_uint16_t    ac_scale[64];
  unsigned char   loop_filter_limits[64];
  th_quant_ranges qi_ranges[2][3];
}th_quant_info;



#define TH_NHUFFMAN_TABLES (80)

#define TH_NDCT_TOKENS     (32)

typedef struct{
  ogg_uint32_t pattern;
  int          nbits;
}th_huff_code;



extern const char *th_version_string(void);
extern ogg_uint32_t th_version_number(void);
extern ogg_int64_t th_granule_frame(void *_encdec,ogg_int64_t _granpos);
extern double th_granule_time(void *_encdec,ogg_int64_t _granpos);
extern int th_packet_isheader(ogg_packet *_op);
extern int th_packet_iskeyframe(ogg_packet *_op);
extern void th_info_init(th_info *_info);
extern void th_info_clear(th_info *_info);

extern void th_comment_init(th_comment *_tc);
extern void th_comment_add(th_comment *_tc, char *_comment);
extern void th_comment_add_tag(th_comment *_tc,char *_tag,char *_val);
extern char *th_comment_query(th_comment *_tc,char *_tag,int _count);
extern int th_comment_query_count(th_comment *_tc,char *_tag);
extern void th_comment_clear(th_comment *_tc);



#if defined(__cplusplus)
}
#endif

#endif

---