diff options
Diffstat (limited to 'debian/transcode/transcode-1.1.7/libtc/ratiocodes.c')
| -rw-r--r-- | debian/transcode/transcode-1.1.7/libtc/ratiocodes.c | 296 |
1 files changed, 296 insertions, 0 deletions
diff --git a/debian/transcode/transcode-1.1.7/libtc/ratiocodes.c b/debian/transcode/transcode-1.1.7/libtc/ratiocodes.c new file mode 100644 index 00000000..0975266e --- /dev/null +++ b/debian/transcode/transcode-1.1.7/libtc/ratiocodes.c @@ -0,0 +1,296 @@ +/* + * ratiocodes.c -- 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/>. + */ + + + +#include "libtc.h" +#include "ratiocodes.h" + +#include <stdlib.h> +#include <math.h> + + +#define TABLE_LEN(tab) (sizeof((tab))/sizeof((tab)[0])) + +/* WARNING: this table MUST BE in frc order */ +static const double frc_table[16] = { + 0, + (24000.0/1001.0), + 24, + 25, + (30000.0/1001.0), + 30, + 50, + (2*(30000.0/1001.0)), + 60, + 1, + 5, + 10, + 12, + 15, + 0, + 0 +}; + +/* WARNING: this table MUST BE in asr order */ +static const double asr_table[8] = { + 0.0, + 1.0, + (4.0/3.0), + (16.0/9.0), + (221.0/100.0), + 0.0, + 0.0, + 0.0, +}; + + +/* WARNING: this table MUST BE in frc order */ +static const TCPair frc_ratios[16] = { + { 0, 0 }, + { 24000, 1001 }, + { 24000, 1000 }, + { 25000, 1000 }, + { 30000, 1001 }, + { 30000, 1000 }, + { 50000, 1000 }, + { 60000, 1001 }, + { 60000, 1000 }, + /* XXX */ + { 1000, 1000 }, + { 5000, 1000 }, + { 10000, 1000 }, + { 12000, 1000 }, + { 15000, 1000 }, + /* XXX */ + { 0, 0 }, + { 0, 0 }, +}; + +/* WARNING: this table MUST BE in asr order */ +static const TCPair asr_ratios[8] = { + { 0, 0 }, + { 1, 1 }, + { 4, 3 }, + { 16, 9 }, + { 221, 100 }, + { 0, 0 }, + { 0, 0 }, + { 0, 0 }, + /* + * XXX: import/tcprobe.c also claims that + * asr == 8 and asr == 12 are 4:3. + * Need further investigation. + */ +}; + +static const TCPair par_ratios[8] = { + { 1, 1 }, + { 1, 1 }, + { 1200, 1100 }, + { 1000, 1100 }, + { 1600, 1100 }, + { 4000, 3300 }, + { 1, 1 }, + { 1, 1 } +}; + +/*************************************************************************/ + + +const char *tc_asr_code_describe(int asr_code) +{ + switch (asr_code) { + case 1: + return "encoded @ 1:1"; + case 2: + return "encoded @ 4:3"; + case 3: + return "encoded @ 16:9"; + case 4: + return "encoded @ 2.21:1"; + case 8: + return "encoded @ 4:3"; + case 12: + return "encoded @ 4:3"; + } + return "encoded @ UNKNOWN"; +} + + +#define DELTA 0.0005 +static int tc_guess_code_from_value(const double *pairs, size_t len, + int *code, double val) +{ + int idx = TC_NULL_MATCH, i = 0; + double mindiff = DELTA; + + for (i = 0; i < len; i++) { + double diff = fabs(pairs[i] - val); + if (diff < mindiff) { + mindiff = diff; + idx = i; + } + } + if (code != NULL && idx != TC_NULL_MATCH) { + *code = idx; + } + return idx; +} +#undef DELTA + + +int tc_asr_code_from_value(int *asr_code, double ratio) +{ + return tc_guess_code_from_value(asr_table, TABLE_LEN(frc_table), + asr_code, ratio); +} + + +int tc_frc_code_from_value(int *frc_code, double fps) +{ + return tc_guess_code_from_value(frc_table, TABLE_LEN(frc_table), + frc_code, fps); +} + + +int tc_frc_code_to_value(int frc_code, double *fps) +{ + if ((fps != NULL && frc_code >= 0) + && frc_code <= TABLE_LEN(frc_table)) { + *fps = frc_table[frc_code]; + return 0; + } + return TC_NULL_MATCH; +} + +/* + * match_ratio: + * helper for various detection functions. Scans a ratio + * table (that MUST be in frc order) looking for corrispondences + * between a ratio and a ratio code. + * + * Parameters: + * pairs: pointer to an array of TCPair to scan + * len: number of pairs to consider + * n: numerator of ratio to look for. Use TC_NULL_MATCH + * if this function must look for a corrispondency of code + * and not for a corrispondency of ratio. + * d: denominator of ratio to look for. Use TC_NULL_MATCH + * if this function must look for a corrispondency of code + * and not for a corrispondency of ratio. + * code: code of ratio to look for. Use TC_NULL_MATCH if this function + * must look for a corrispondency of ratio. + * Return Value: + * TC_NULL_MATCH if input parameter(s) isn't known. + * >= 0 index in table of given corrispondency. + * Precondintions: + * given pairs table MUST BE in code (frc, asr) order. + * pairs != NULL. + */ +static int match_ratio(const TCPair *pairs, size_t len, + int n, int d, int code) +{ + int i = 0, r = TC_NULL_MATCH; + for (i = 0; i < len; i++) { + if (i == code) { + r = i; + break; + } + if (n == pairs[i].a && d == pairs[i].b) { + r = i; + break; + } + } + return r; +} + +static int select_table(TCRatioCode rc, const TCPair **table, size_t *len) +{ + int ret = 0; + + switch (rc) { + case TC_FRC_CODE: + *table = frc_ratios; + *len = TABLE_LEN(frc_ratios); + break; + case TC_ASR_CODE: + *table = asr_ratios; + *len = TABLE_LEN(asr_ratios); + break; + case TC_PAR_CODE: + *table = par_ratios; + *len = TABLE_LEN(par_ratios); + break; + default: + *table = NULL; + *len = 0; + ret = TC_NULL_MATCH; + } + return ret; +} + +int tc_code_from_ratio(TCRatioCode rc, int *out_code, int in_n, int in_d) +{ + int code = TC_NULL_MATCH; + const TCPair *table = NULL; + size_t len = 0; + + select_table(rc, &table, &len); + if (table != NULL) { + code = match_ratio(table, len, in_n, in_d, TC_NULL_MATCH); + if (out_code != NULL && code != TC_NULL_MATCH) { + *out_code = code; + } + } + return code; +} + + +int tc_code_to_ratio(TCRatioCode rc, int in_code, int *out_n, int *out_d) +{ + int code = TC_NULL_MATCH; + const TCPair *table = NULL; + size_t len = 0; + + select_table(rc, &table, &len); + if (table != NULL) { + code = match_ratio(table, len, + TC_NULL_MATCH, TC_NULL_MATCH, in_code); + if ((out_n != NULL && out_d != NULL) && code != TC_NULL_MATCH) { + *out_n = table[code].a; + *out_d = table[code].b; + } + } + return code; +} + +/*************************************************************************/ + +/* + * Local variables: + * c-file-style: "stroustrup" + * c-file-offsets: ((case-label . *) (statement-case-intro . *)) + * indent-tabs-mode: nil + * End: + * + * vim: expandtab shiftwidth=4: + */ |