---
libavcodec/ccaption_dec.c | 43 +++++++------------------------------------
1 file changed, 7 insertions(+), 36 deletions(-)
diff --git a/libavcodec/ccaption_dec.c b/libavcodec/ccaption_dec.c
index 9f67caa..1fdf7ed 100644
--- a/libavcodec/ccaption_dec.c
+++ b/libavcodec/ccaption_dec.c
@@ -101,40 +101,6 @@ static const unsigned char pac2_attribs[32][3] = // Color,
font, ident
/* total 32 entries */
};
-/* 0-255 needs 256 spaces */
-static const uint8_t parity_table[256] = { 0, 1, 1, 0, 1, 0, 0, 1,
- 1, 0, 0, 1, 0, 1, 1, 0,
- 1, 0, 0, 1, 0, 1, 1, 0,
- 0, 1, 1, 0, 1, 0, 0, 1,
- 1, 0, 0, 1, 0, 1, 1, 0,
- 0, 1, 1, 0, 1, 0, 0, 1,
- 0, 1, 1, 0, 1, 0, 0, 1,
- 1, 0, 0, 1, 0, 1, 1, 0,
- 1, 0, 0, 1, 0, 1, 1, 0,
- 0, 1, 1, 0, 1, 0, 0, 1,
- 0, 1, 1, 0, 1, 0, 0, 1,
- 1, 0, 0, 1, 0, 1, 1, 0,
- 0, 1, 1, 0, 1, 0, 0, 1,
- 1, 0, 0, 1, 0, 1, 1, 0,
- 1, 0, 0, 1, 0, 1, 1, 0,
- 0, 1, 1, 0, 1, 0, 0, 1,
- 1, 0, 0, 1, 0, 1, 1, 0,
- 0, 1, 1, 0, 1, 0, 0, 1,
- 0, 1, 1, 0, 1, 0, 0, 1,
- 1, 0, 0, 1, 0, 1, 1, 0,
- 0, 1, 1, 0, 1, 0, 0, 1,
- 1, 0, 0, 1, 0, 1, 1, 0,
- 1, 0, 0, 1, 0, 1, 1, 0,
- 0, 1, 1, 0, 1, 0, 0, 1,
- 0, 1, 1, 0, 1, 0, 0, 1,
- 1, 0, 0, 1, 0, 1, 1, 0,
- 1, 0, 0, 1, 0, 1, 1, 0,
- 0, 1, 1, 0, 1, 0, 0, 1,
- 1, 0, 0, 1, 0, 1, 1, 0,
- 0, 1, 1, 0, 1, 0, 0, 1,
- 0, 1, 1, 0, 1, 0, 0, 1,
- 1, 0, 0, 1, 0, 1, 1, 0 };
-
struct Screen {
/* +1 is used to compensate null character of string */
uint8_t characters[SCREEN_ROWS][SCREEN_COLUMNS+1];
@@ -221,6 +187,11 @@ static int write_char (CCaptionSubContext *ctx, char
*row,uint8_t col, char ch)
}
}
+static inline int get_parity(uint8_t x)
+{
+ return (0x6996966996696996ULL >> (x & 63) ^ (x>>7) ^ (x>>6)) & 1;
+}
+
/**
* This function after validating parity bit, also remove it from data pair.
* The first byte doesn't pass parity, we replace it with a solid blank
@@ -238,10 +209,10 @@ static int validate_cc_data_pair (uint8_t *cc_data_pair)
// if EIA-608 data then verify parity.
if (cc_type==0 || cc_type==1) {
- if (!parity_table[cc_data_pair[2]]) {
+ if (!get_parity(cc_data_pair[2])) {
return AVERROR_INVALIDDATA;
}
- if (!parity_table[cc_data_pair[1]]) {
+ if (!get_parity(cc_data_pair[1])) {
cc_data_pair[1]=0x7F;
}
}
--
2.6.4
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