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/*
* ratiocodes.h -- database for all ratio/codes (asr, sar, dar, frc...)
* used in transcode
* (C) 2005-2010 - Francesco Romani <fromani -at- gmail -dot- com>
*
* This file is part of transcode, a video stream processing tool.
*
* transcode is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* transcode is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef RATIOCODES_H
#define RATIOCODES_H
/*
* same ratio codes (i.e.: code=3) have different meaning in
* different contexts, so we have this enum to let the
* tc_code_{from,to}_ratio functions distinguish operational
* context.
*/
typedef enum tccoderatio_ TCRatioCode;
enum tccoderatio_ {
TC_FRC_CODE = 1, /* frame ratio */
TC_ASR_CODE, /* (display?) aspect ratio */
TC_PAR_CODE, /* pixel aspect ratio */
};
typedef struct tcpair_ TCPair;
struct tcpair_ {
int a; /* numerator, width... */
int b; /* denominator, height... */
};
#define TC_FRC_FPS_TO_RATIO(fps, pn, pd) \
do { \
*(pn) = (int)((fps) * 1000.0); \
*(pd) = 1000; \
} while(0)
/*
* TCPair VS int/int dilemma:
*
* Why don't use out TCPair instead of int/int couples in
* functions interface below?
* this code (and the whole transcode in general) need to interact
* with a broad variety of foreign code with various conventions,
* interface, styles and so on. I've no *YET* found a clean way
* to use a custom struct (TCPair) for those situations without
* requiring to use a temporary variable, that looks quite
* clumsy to me. So I've chosen to fall back to minimum
* common denominator, that is a couple of int or pointer
* to ints.
*
* Of course this can change if a better and cleanest solution
* pops out :)
*
* BTW, TCPair is extensively used in internal processing and
* in private code.
*/
/*************************************************************************/
/*
* tc_asr_code_describe:
* provides a descriptive, human readable string of given ASR code.
*
* Parameters:
* asr_code: the ASR code.
* Return Value:
* A constant string describing the given ASR code.
* There is NO NEED (and it is WRONG to do so) to free() it.
* Returned string is guaranteed to be valid at least until
* the next call to this function.
*/
const char *tc_asr_code_describe(int asr_code);
/*
* tc_asr_code_from_value:
* detect the right aspect ratio code (asr) given an aspect ratio value
* as real number.
*
* Parameters:
* asr_code: pointer to integer where detected asr code will be stored.
* Can be NULL: if so, asr code will be detected but not
* stored.
* ratio: value of frame rate, as real number.
* Return Value:
* TC_NULL_MATCH if input value isn't known
* >= 0 otherwise
*/
int tc_asr_code_from_value(int *asr_code, double ratio);
/*
* tc_frc_code_from_value:
* detect the right frame ratio code (frc) given a frame rate value as
* real number.
*
* Parameters:
* frc_code: pointer to integer where detected frc code will be stored.
* Can be NULL: if so, frc code will be detected but not
* stored.
* fps: value of frame rate, as real number.
* Return Value:
* TC_NULL_MATCH if input value isn't known
* >= 0 otherwise
*/
int tc_frc_code_from_value(int *frc_code, double fps);
/*
* tc_frc_code_to_value:
* detect the right frame ratio value as real number given a frame rate
* code (frc).
*
* Parameters:
* frc_code: frame rate code.
* fps: pointer to double where detected frc value will be stored.
* Can be NULL: if so, frc value will be detected but not
* stored.
* Return Value:
* TC_NULL_MATCH if input value isn't known
* >= 0 otherwise
*/
int tc_frc_code_to_value(int frc_code, double *fps);
/*
* tc_code_from_ratio:
* detect the right code in a specificied domain given a fraction as
* pair of integers.
*
* Parameters:
* rc: select operational domain. See definition of
* TCRatioCode above to see avalaible domains.
* code: pointer to integer where detected code will be stored.
* Can be NULL: if so, code will be detected but not
* stored.
* n: numerator of given frame ratio fraction.
* d: denominator of given frame ratio fraction.
* Return Value:
* TC_NULL_MATCH if input value isn't known
* >= 0 otherwise
*/
int tc_code_from_ratio(TCRatioCode rc, int *out_code, int in_n, int in_d);
/*
* tc_frc_code_to_ratio:
* detect the right ratio fraction in a specified domain as pair of
* integers given a ratio code.
*
* Parameters:
* rc: select operational domain. See definition of
* TCRatioCode above to see avalaible domains.
* code: code to be converted in fraction.
* n: pointer to integer where numerator of rate fraction
* will ne stored. Can be NULL: if so, fraction will be
* detected but not stored.
* d: pointer to integer where denominator of frate fraction
* will ne stored. Can be NULL: if so, fraction will be
* detected but not stored.
* Return Value:
* TC_NULL_MATCH if input value isn't known
* >= 0 otherwise
*/
int tc_code_to_ratio(TCRatioCode rc, int in_code, int *out_n, int *out_d);
/* macro goodies */
#define tc_frc_code_from_ratio(frc, n, d) \
tc_code_from_ratio(TC_FRC_CODE, frc, n, d)
#define tc_frc_code_to_ratio(frc, n, d) \
tc_code_to_ratio(TC_FRC_CODE, frc, n, d)
#define tc_asr_code_from_ratio(asr, n, d) \
tc_code_from_ratio(TC_ASR_CODE, asr, n, d)
#define tc_asr_code_to_ratio(asr, n, d) \
tc_code_to_ratio(TC_ASR_CODE, asr, n, d)
#define tc_par_code_from_ratio(par, n, d) \
tc_code_from_ratio(TC_PAR_CODE, par, n, d)
#define tc_par_code_to_ratio(par, n, d) \
tc_code_to_ratio(TC_PAR_CODE, par, n, d)
#endif /* RATIOCODES_H */