libtheora: codec.h Source File

libtheora 1.1.1

codec.h
Go to the documentation of this file.
1 /********************************************************************
2 * *
3 * THIS FILE IS PART OF THE OggTheora SOFTWARE CODEC SOURCE CODE. *
4 * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS *
5 * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
6 * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. *
7 * *
8 * THE Theora SOURCE CODE IS COPYRIGHT (C) 2002-2009 *
9 * by the Xiph.Org Foundation http://www.xiph.org/ *
10 * *
11 ********************************************************************
12
13 function:
14 last mod: $Id: theora.h,v 1.8 2004/03/15 22:17:32 derf Exp $
15
16 ********************************************************************/
17
62 #if !defined(_O_THEORA_CODEC_H_)
63 # define _O_THEORA_CODEC_H_ (1)
64 # include <ogg/ogg.h>
65
66 #if defined(__cplusplus)
67 extern "C" {
68 #endif
69
70
71
75 #define TH_EFAULT (-1)
76
77 #define TH_EINVAL (-10)
78
79 #define TH_EBADHEADER (-20)
80
81 #define TH_ENOTFORMAT (-21)
82
83 #define TH_EVERSION (-22)
84
85 #define TH_EIMPL (-23)
86
87 #define TH_EBADPACKET (-24)
88
91 #define TH_DUPFRAME (1)
92
98 typedef enum{
101 TH_CS_UNSPECIFIED,
103 TH_CS_ITU_REC_470M,
105 TH_CS_ITU_REC_470BG,
107 TH_CS_NSPACES
108 }th_colorspace;
109
114 typedef enum{
118 TH_PF_420,
120 TH_PF_RSVD,
124 TH_PF_422,
127 TH_PF_444,
129 TH_PF_NFORMATS
130 }th_pixel_fmt;
131
132
133
142 typedef struct{
144 int width;
146 int height;
148 int stride;
150 unsigned char *data;
151 }th_img_plane;
152
168 typedef th_img_plane th_ycbcr_buffer[3];
169
204 typedef struct{
208 unsigned char version_major;
209 unsigned char version_minor;
210 unsigned char version_subminor;
214 ogg_uint32_t frame_width;
217 ogg_uint32_t frame_height;
220 ogg_uint32_t pic_width;
223 ogg_uint32_t pic_height;
227 ogg_uint32_t pic_x;
235 ogg_uint32_t pic_y;
240 ogg_uint32_t fps_numerator;
241 ogg_uint32_t fps_denominator;
252 ogg_uint32_t aspect_numerator;
253 ogg_uint32_t aspect_denominator;
256 th_colorspace colorspace;
258 th_pixel_fmt pixel_fmt;
262 int target_bitrate;
268 /*Currently this is set so that a qi of 0 corresponds to distortions of 24
269 times the JND, and each increase by 16 halves that value.
270 This gives us fine discrimination at low qualities, yet effective rate
271 control at high qualities.
272 The qi value 63 is special, however.
273 For this, the highest quality, we use one half of a JND for our threshold.
274 Due to the lower bounds placed on allowable quantizers in Theora, we will
275 not actually be able to achieve quality this good, but this should
276 provide as close to visually lossless quality as Theora is capable of.
277 We could lift the quantizer restrictions without breaking VP3.1
278 compatibility, but this would result in quantized coefficients that are
279 too large for the current bitstream to be able to store.
280 We'd have to redesign the token syntax to store these large coefficients,
281 which would make transcoding complex.*/
282 int quality;
296 int keyframe_granule_shift;
297 }th_info;
298
323 typedef struct th_comment{
325 char **user_comments;
327 int *comment_lengths;
329 int comments;
332 char *vendor;
333 }th_comment;
334
335
336
338 typedef unsigned char th_quant_base[64];
339
341 typedef struct{
343 int nranges;
346 const int *sizes;
349 const th_quant_base *base_matrices;
350 }th_quant_ranges;
351
409 typedef struct{
411 ogg_uint16_t dc_scale[64];
413 ogg_uint16_t ac_scale[64];
415 unsigned char loop_filter_limits[64];
417 th_quant_ranges qi_ranges[2][3];
418 }th_quant_info;
419
420
421
423 #define TH_NHUFFMAN_TABLES (80)
424
425 #define TH_NDCT_TOKENS (32)
426
438 typedef struct{
441 ogg_uint32_t pattern;
444 int nbits;
445 }th_huff_code;
446
447
448
456 extern const char *th_version_string(void);
466 extern ogg_uint32_t th_version_number(void);
476 extern ogg_int64_t th_granule_frame(void *_encdec,ogg_int64_t _granpos);
488 extern double th_granule_time(void *_encdec,ogg_int64_t _granpos);
498 extern int th_packet_isheader(ogg_packet *_op);
509 extern int th_packet_iskeyframe(ogg_packet *_op);
519 extern void th_info_init(th_info *_info);
524 extern void th_info_clear(th_info *_info);
525
530 extern void th_comment_init(th_comment *_tc);
540 extern void th_comment_add(th_comment *_tc, char *_comment);
551 extern void th_comment_add_tag(th_comment *_tc,char *_tag,char *_val);
567 extern char *th_comment_query(th_comment *_tc,char *_tag,int _count);
575 extern int th_comment_query_count(th_comment *_tc,char *_tag);
581 extern void th_comment_clear(th_comment *_tc);
584
585
586
587 #if defined(__cplusplus)
588 }
589 #endif
590
591 #endif
TH_PF_420
@ TH_PF_420
Chroma decimation by 2 in both the X and Y directions (4:2:0).
Definition: codec.h:118
th_img_plane::stride
int stride
The offset in bytes between successive rows.
Definition: codec.h:148
th_info::pic_y
ogg_uint32_t pic_y
The Y offset of the displayed picture.
Definition: codec.h:235
th_comment::user_comments
char ** user_comments
The array of comment string vectors.
Definition: codec.h:325
th_quant_ranges::base_matrices
const th_quant_base * base_matrices
nranges +1 base matrices.
Definition: codec.h:349
th_info
Theora bitstream information.
Definition: codec.h:204
TH_CS_ITU_REC_470M
@ TH_CS_ITU_REC_470M
A color space designed for NTSC content.
Definition: codec.h:103
TH_PF_RSVD
@ TH_PF_RSVD
Currently reserved.
Definition: codec.h:120
th_info::fps_numerator
ogg_uint32_t fps_numerator
Definition: codec.h:240
th_comment_add_tag
void th_comment_add_tag(th_comment *_tc, char *_tag, char *_val)
Add a comment to an initialized th_comment structure.
th_info_clear
void th_info_clear(th_info *_info)
Clears a th_info structure.
th_colorspace
th_colorspace
The currently defined color space tags.
Definition: codec.h:98
TH_PF_NFORMATS
@ TH_PF_NFORMATS
The total number of currently defined pixel formats.
Definition: codec.h:129
th_img_plane::width
int width
The width of this plane.
Definition: codec.h:144
TH_PF_444
@ TH_PF_444
No chroma decimation (4:4:4).
Definition: codec.h:127
th_info::fps_denominator
ogg_uint32_t fps_denominator
Definition: codec.h:241
th_comment::comment_lengths
int * comment_lengths
An array of the corresponding length of each vector, in bytes.
Definition: codec.h:327
th_quant_ranges::nranges
int nranges
The number of ranges in the set.
Definition: codec.h:343
th_ycbcr_buffer
th_img_plane th_ycbcr_buffer[3]
A complete image buffer for an uncompressed frame.
Definition: codec.h:168
th_info::frame_height
ogg_uint32_t frame_height
The encoded frame height.
Definition: codec.h:217
TH_CS_UNSPECIFIED
@ TH_CS_UNSPECIFIED
The color space was not specified at the encoder.
Definition: codec.h:101
th_info::aspect_denominator
ogg_uint32_t aspect_denominator
Definition: codec.h:253
TH_CS_ITU_REC_470BG
@ TH_CS_ITU_REC_470BG
A color space designed for PAL/SECAM content.
Definition: codec.h:105
th_comment_add
void th_comment_add(th_comment *_tc, char *_comment)
Add a comment to an initialized th_comment structure.
th_info::version_minor
unsigned char version_minor
Definition: codec.h:209
th_info::colorspace
th_colorspace colorspace
The color space.
Definition: codec.h:256
th_img_plane::data
unsigned char * data
A pointer to the beginning of the first row.
Definition: codec.h:150
th_granule_frame
ogg_int64_t th_granule_frame(void *_encdec, ogg_int64_t _granpos)
Converts a granule position to an absolute frame index, starting at 0.
TH_PF_422
@ TH_PF_422
Chroma decimation by 2 in the X direction (4:2:2).
Definition: codec.h:124
th_quant_info
A complete set of quantization parameters.
Definition: codec.h:409
th_pixel_fmt
th_pixel_fmt
The currently defined pixel format tags.
Definition: codec.h:114
th_info::pic_width
ogg_uint32_t pic_width
The displayed picture width.
Definition: codec.h:220
th_info::pic_height
ogg_uint32_t pic_height
The displayed picture height.
Definition: codec.h:223
th_huff_code::nbits
int nbits
The number of bits in the code.
Definition: codec.h:444
th_info::version_major
unsigned char version_major
Definition: codec.h:208
th_comment
The comment information.
Definition: codec.h:323
th_version_number
ogg_uint32_t th_version_number(void)
Retrieves the library version number.
th_info::target_bitrate
int target_bitrate
The target bit-rate in bits per second.
Definition: codec.h:262
th_quant_ranges::sizes
const int * sizes
The size of each of the nranges ranges.
Definition: codec.h:346
th_quant_ranges
A set of qi ranges.
Definition: codec.h:341
th_info::pic_x
ogg_uint32_t pic_x
The X offset of the displayed picture.
Definition: codec.h:227
th_quant_base
unsigned char th_quant_base[64]
A single base matrix.
Definition: codec.h:338
th_img_plane
A buffer for a single color plane in an uncompressed image.
Definition: codec.h:142
th_info::frame_width
ogg_uint32_t frame_width
The encoded frame width.
Definition: codec.h:214
th_comment::vendor
char * vendor
The null-terminated vendor string.
Definition: codec.h:332
th_packet_isheader
int th_packet_isheader(ogg_packet *_op)
Determines whether a Theora packet is a header or not.
th_version_string
const char * th_version_string(void)
Retrieves a human-readable string to identify the library vendor and version.
th_info::aspect_numerator
ogg_uint32_t aspect_numerator
Definition: codec.h:252
th_comment
struct th_comment th_comment
The comment information.
TH_CS_NSPACES
@ TH_CS_NSPACES
The total number of currently defined color spaces.
Definition: codec.h:107
th_packet_iskeyframe
int th_packet_iskeyframe(ogg_packet *_op)
Determines whether a theora packet is a key frame or not.
th_comment_query_count
int th_comment_query_count(th_comment *_tc, char *_tag)
Look up the number of instances of a tag.
th_huff_code::pattern
ogg_uint32_t pattern
The bit pattern for the code, with the LSbit of the pattern aligned in the LSbit of the word.
Definition: codec.h:441
th_info::quality
int quality
The target quality level.
Definition: codec.h:282
th_comment_query
char * th_comment_query(th_comment *_tc, char *_tag, int _count)
Look up a comment value by its tag.
th_img_plane::height
int height
The height of this plane.
Definition: codec.h:146
th_info::pixel_fmt
th_pixel_fmt pixel_fmt
The pixel format.
Definition: codec.h:258
th_info_init
void th_info_init(th_info *_info)
Initializes a th_info structure.
th_info::keyframe_granule_shift
int keyframe_granule_shift
The amount to shift to extract the last keyframe number from the granule position.
Definition: codec.h:296
th_info::version_subminor
unsigned char version_subminor
Definition: codec.h:210
th_huff_code
A Huffman code for a Theora DCT token.
Definition: codec.h:438
th_comment_clear
void th_comment_clear(th_comment *_tc)
Clears a th_comment structure.
th_comment::comments
int comments
The total number of comment strings.
Definition: codec.h:329
th_comment_init
void th_comment_init(th_comment *_tc)
Initialize a th_comment structure.
th_granule_time
double th_granule_time(void *_encdec, ogg_int64_t _granpos)
Converts a granule position to an absolute time in seconds.