diff options
| author | Michael Niedermayer <michaelni@gmx.at> | 2014-04-19 00:29:57 +0200 |
|---|---|---|
| committer | Michael Niedermayer <michaelni@gmx.at> | 2014-04-19 01:22:06 +0200 |
| commit | a47cc877a072bf6dc0d2c6ff2e138d685b162470 (patch) | |
| tree | 012277422cbec567675e6490a175700f828dd12d | |
| parent | 3a1feb01da6149170a442111ce6419fff22fffba (diff) | |
avfilter/vf_rotate: increase fixed point precision
This ensures int_sins output doesnt have "random" lsbs
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
| -rw-r--r-- | libavfilter/vf_rotate.c | 17 | ||||
| -rw-r--r-- | tests/ref/fate/filter-pixfmts-rotate | 40 |
2 files changed, 29 insertions, 28 deletions
diff --git a/libavfilter/vf_rotate.c b/libavfilter/vf_rotate.c index e242ee2dfa..2f55bfc1cc 100644 --- a/libavfilter/vf_rotate.c +++ b/libavfilter/vf_rotate.c @@ -252,11 +252,12 @@ static int config_props(AVFilterLink *outlink) } #define FIXP (1<<16) -#define INT_PI 205887 //(M_PI * FIXP) +#define FIXP2 (1<<20) +#define INT_PI 3294199 //(M_PI * FIXP2) /** * Compute the sin of a using integer values. - * Input and output values are scaled by FIXP. + * Input is scaled by FIXP2 and output values are scaled by FIXP. */ static int64_t int_sin(int64_t a) { @@ -268,13 +269,13 @@ static int64_t int_sin(int64_t a) if (a >= INT_PI*3/2) a -= 2*INT_PI; // -PI/2 .. 3PI/2 if (a >= INT_PI/2 ) a = INT_PI - a; // -PI/2 .. PI/2 - /* compute sin using Taylor series approximated to the third term */ - a2 = (a*a)/FIXP; - for (i = 2; i < 7; i += 2) { + /* compute sin using Taylor series approximated to the fifth term */ + a2 = (a*a)/(FIXP2); + for (i = 2; i < 11; i += 2) { res += a; - a = -a*a2 / (FIXP*i*(i+1)); + a = -a*a2 / (FIXP2*i*(i+1)); } - return res; + return (res + 8)>>4; } /** @@ -402,7 +403,7 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *in) av_log(ctx, AV_LOG_DEBUG, "n:%f time:%f angle:%f/PI\n", rot->var_values[VAR_N], rot->var_values[VAR_T], rot->angle/M_PI); - angle_int = res * FIXP; + angle_int = res * FIXP * 16; s = int_sin(angle_int); c = int_sin(angle_int + INT_PI/2); diff --git a/tests/ref/fate/filter-pixfmts-rotate b/tests/ref/fate/filter-pixfmts-rotate index 0438aefca2..1a0bf24e29 100644 --- a/tests/ref/fate/filter-pixfmts-rotate +++ b/tests/ref/fate/filter-pixfmts-rotate @@ -1,20 +1,20 @@ -0bgr 1040a5c4645582fc271f7be40ea5aaf7 -0rgb 7f21fcf8fd658de854b75dd8c47b0b00 -abgr 24f441d2e6e67cae2d3451aa1dad23a7 -argb 993002f41f621d04cd76278e466c03eb -bgr0 efe11efe2840fa84ee95cdb913463bc1 -bgr24 d0f449e8b38e07c947bd808f441a8ace -bgra 54cebf01881cb63ec3727f7cc23b0a6b -gbrap 6d69c0cd0cba6300065f8d990e35b081 -gbrp db3b6345d2a5c0fb524f93486d97193e -gray 5a896c38449a0fb08129a7394952eb31 -rgb0 c29f92ff5224044c7272c763fa5321e6 -rgb24 739f0eb47e76ce5c87354d5631ac2d5b -rgba f25570a798f24e8174729d978872c272 -yuv410p 22e673170464119cafb1a973c5a8080c -yuv420p afed4567a1b2d54ca9bc87bbdfff9a34 -yuv444p df57aba68928092b54f6b75ab01e3110 -yuva420p ad9bdb4f21855550a6f94e2d96588097 -yuva444p b6a345f46ef75814033f733ccb4da42e -yuvj420p ccc0724c2ff91daa3848db1f4d91d010 -yuvj444p 9165b6e7c647c93cd24011d931890edb +0bgr 8bce6fc2b0532e6dceee3bae394c170b +0rgb b1f893e98c87f32d0131f7f019bd3c10 +abgr a5b742253d41be91ee1726980c39fca5 +argb deb903538e653598c119bfcee2aee651 +bgr0 bdf68c2709492abc5d05cbae373dee7d +bgr24 e669ad05a12b8a5f853b599f38fa9725 +bgra 2353862686c14bbfe3a103aaec8ab6ed +gbrap 4d19ce999a450498fd71c3764b2f9aa7 +gbrp 149393d82ef85a102f62a78aeccc86b6 +gray b40cc829f4310691c717a8162c945fc2 +rgb0 e7b835d6ddfcfe87632604a81c2468e7 +rgb24 1b1b62bd26d83988f4ec51584ebea300 +rgba f0bdbad87cace97926025917a010ffa2 +yuv410p 98b7126c5e00687e033da047ec44dc59 +yuv420p c67848288b31393a1045efb335c533ce +yuv444p 2d017f98f986810246068d2a3af3049b +yuva420p 1ee052f2688c6caf9f08cc9ede7c133e +yuva444p dd7bccf95744e374295be468e882b96d +yuvj420p 34aa87584344e7ba0dbe92f89d865de7 +yuvj444p d1b2eb2ea933839a2cb587043a789313 |