Fixed-point support in fft-test

Signed-off-by: Mans Rullgard <mans@mansr.com>

libavcodec/Makefile

@@ -656,7 +656,7 @@ SKIPHEADERS                            += mpegaudio3.h
 
 EXAMPLES = api
 
-TESTPROGS = cabac dct eval fft h264 iirfilter rangecoder snow
+TESTPROGS = cabac dct eval fft fft-fixed h264 iirfilter rangecoder snow
 TESTPROGS-$(HAVE_MMX) += motion
 TESTOBJS = dctref.o
 

libavcodec/fft-fixed-test.c

+/*
+ * This file is part of Libav.
+ *
+ * Libav is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * Libav 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#define CONFIG_FFT_FLOAT 0
+#include "fft-test.c"

libavcodec/fft-test.c

@@ -27,8 +27,10 @@
 #include "libavutil/lfg.h"
 #include "libavutil/log.h"
 #include "fft.h"
+#if CONFIG_FFT_FLOAT
 #include "dct.h"
 #include "rdft.h"
+#endif
 #include <math.h>
 #include <unistd.h>
 #include <sys/time.h>
@@ -47,7 +49,19 @@
    pim += (MUL16(are, bim) + MUL16(bre, aim));\
 }
 
-FFTComplex *exptab;
+#if CONFIG_FFT_FLOAT
+#   define RANGE 1.0
+#   define REF_SCALE(x, bits)  (x)
+#   define FMT "%10.6f"
+#else
+#   define RANGE 16384
+#   define REF_SCALE(x, bits) ((x) / (1<<(bits)))
+#   define FMT "%6d"
+#endif
+
+struct {
+    float re, im;
+} *exptab;
 
 static void fft_ref_init(int nbits, int inverse)
 {
@@ -55,7 +69,7 @@ static void fft_ref_init(int nbits, int inverse)
     double c1, s1, alpha;
 
     n = 1 << nbits;
-    exptab = av_malloc((n / 2) * sizeof(FFTComplex));
+    exptab = av_malloc((n / 2) * sizeof(*exptab));
 
     for (i = 0; i < (n/2); i++) {
         alpha = 2 * M_PI * (float)i / (float)n;
@@ -92,12 +106,12 @@ static void fft_ref(FFTComplex *tabr, FFTComplex *tab, int nbits)
             CMAC(tmp_re, tmp_im, c, s, q->re, q->im);
             q++;
         }
-        tabr[i].re = tmp_re;
-        tabr[i].im = tmp_im;
+        tabr[i].re = REF_SCALE(tmp_re, nbits);
+        tabr[i].im = REF_SCALE(tmp_im, nbits);
     }
 }
 
-static void imdct_ref(float *out, float *in, int nbits)
+static void imdct_ref(FFTSample *out, FFTSample *in, int nbits)
 {
     int n = 1<<nbits;
     int k, i, a;
@@ -110,12 +124,12 @@ static void imdct_ref(float *out, float *in, int nbits)
             f = cos(M_PI * a / (double)(2 * n));
             sum += f * in[k];
         }
-        out[i] = -sum;
+        out[i] = REF_SCALE(-sum, nbits - 2);
     }
 }
 
 /* NOTE: no normalisation by 1 / N is done */
-static void mdct_ref(float *output, float *input, int nbits)
+static void mdct_ref(FFTSample *output, FFTSample *input, int nbits)
 {
     int n = 1<<nbits;
     int k, i;
@@ -128,10 +142,11 @@ static void mdct_ref(float *output, float *input, int nbits)
             a = (2*M_PI*(2*i+1+n/2)*(2*k+1) / (4 * n));
             s += input[i] * cos(a);
         }
-        output[k] = s;
+        output[k] = REF_SCALE(s, nbits - 1);
     }
 }
 
+#if CONFIG_FFT_FLOAT
 static void idct_ref(float *output, float *input, int nbits)
 {
     int n = 1<<nbits;
@@ -164,11 +179,12 @@ static void dct_ref(float *output, float *input, int nbits)
         output[k] = s;
     }
 }
+#endif
 
 
-static float frandom(AVLFG *prng)
+static FFTSample frandom(AVLFG *prng)
 {
-    return (int16_t)av_lfg_get(prng) / 32768.0;
+    return (int16_t)av_lfg_get(prng) / 32768.0 * RANGE;
 }
 
 static int64_t gettime(void)
@@ -178,7 +194,7 @@ static int64_t gettime(void)
     return (int64_t)tv.tv_sec * 1000000 + tv.tv_usec;
 }
 
-static int check_diff(float *tab1, float *tab2, int n, double scale)
+static int check_diff(FFTSample *tab1, FFTSample *tab2, int n, double scale)
 {
     int i;
     double max= 0;
@@ -186,9 +202,9 @@ static int check_diff(float *tab1, float *tab2, int n, double scale)
     int err = 0;
 
     for (i = 0; i < n; i++) {
-        double e= fabsf(tab1[i] - (tab2[i] / scale));
+        double e = fabsf(tab1[i] - (tab2[i] / scale)) / RANGE;
         if (e >= 1e-3) {
-            av_log(NULL, AV_LOG_ERROR, "ERROR %5d: %10.6f %10.6f\n",
+            av_log(NULL, AV_LOG_ERROR, "ERROR %5d: "FMT" "FMT"\n",
                    i, tab1[i], tab2[i]);
             err = 1;
         }
@@ -233,8 +249,10 @@ int main(int argc, char **argv)
     int do_inverse = 0;
     FFTContext s1, *s = &s1;
     FFTContext m1, *m = &m1;
+#if CONFIG_FFT_FLOAT
     RDFTContext r1, *r = &r1;
     DCTContext d1, *d = &d1;
+#endif
     int fft_nbits, fft_size, fft_size_2;
     double scale = 1.0;
     AVLFG prng;
@@ -297,6 +315,7 @@ int main(int argc, char **argv)
         ff_fft_init(s, fft_nbits, do_inverse);
         fft_ref_init(fft_nbits, do_inverse);
         break;
+#if CONFIG_FFT_FLOAT
     case TRANSFORM_RDFT:
         if (do_inverse)
             av_log(NULL, AV_LOG_INFO,"IDFT_C2R");
@@ -312,6 +331,10 @@ int main(int argc, char **argv)
             av_log(NULL, AV_LOG_INFO,"DCT_II");
         ff_dct_init(d, fft_nbits, do_inverse ? DCT_III : DCT_II);
         break;
+#endif
+    default:
+        av_log(NULL, AV_LOG_ERROR, "Requested transform not supported\n");
+        return 1;
     }
     av_log(NULL, AV_LOG_INFO," %d test\n", fft_size);
 
@@ -328,15 +351,15 @@ int main(int argc, char **argv)
     switch (transform) {
     case TRANSFORM_MDCT:
         if (do_inverse) {
-            imdct_ref((float *)tab_ref, (float *)tab1, fft_nbits);
-            m->imdct_calc(m, tab2, (float *)tab1);
-            err = check_diff((float *)tab_ref, tab2, fft_size, scale);
+            imdct_ref((FFTSample *)tab_ref, (FFTSample *)tab1, fft_nbits);
+            m->imdct_calc(m, tab2, (FFTSample *)tab1);
+            err = check_diff((FFTSample *)tab_ref, tab2, fft_size, scale);
         } else {
-            mdct_ref((float *)tab_ref, (float *)tab1, fft_nbits);
+            mdct_ref((FFTSample *)tab_ref, (FFTSample *)tab1, fft_nbits);
 
-            m->mdct_calc(m, tab2, (float *)tab1);
+            m->mdct_calc(m, tab2, (FFTSample *)tab1);
 
-            err = check_diff((float *)tab_ref, tab2, fft_size / 2, scale);
+            err = check_diff((FFTSample *)tab_ref, tab2, fft_size / 2, scale);
         }
         break;
     case TRANSFORM_FFT:
@@ -345,8 +368,9 @@ int main(int argc, char **argv)
         s->fft_calc(s, tab);
 
         fft_ref(tab_ref, tab1, fft_nbits);
-        err = check_diff((float *)tab_ref, (float *)tab, fft_size * 2, 1.0);
+        err = check_diff((FFTSample *)tab_ref, (FFTSample *)tab, fft_size * 2, 1.0);
         break;
+#if CONFIG_FFT_FLOAT
     case TRANSFORM_RDFT:
         if (do_inverse) {
             tab1[         0].im = 0;
@@ -387,6 +411,7 @@ int main(int argc, char **argv)
         }
         err = check_diff((float *)tab_ref, (float *)tab, fft_size, 1.0);
         break;
+#endif
     }
 
     /* do a speed test */
@@ -404,15 +429,16 @@ int main(int argc, char **argv)
                 switch (transform) {
                 case TRANSFORM_MDCT:
                     if (do_inverse) {
-                        m->imdct_calc(m, (float *)tab, (float *)tab1);
+                        m->imdct_calc(m, (FFTSample *)tab, (FFTSample *)tab1);
                     } else {
-                        m->mdct_calc(m, (float *)tab, (float *)tab1);
+                        m->mdct_calc(m, (FFTSample *)tab, (FFTSample *)tab1);
                     }
                     break;
                 case TRANSFORM_FFT:
                     memcpy(tab, tab1, fft_size * sizeof(FFTComplex));
                     s->fft_calc(s, tab);
                     break;
+#if CONFIG_FFT_FLOAT
                 case TRANSFORM_RDFT:
                     memcpy(tab2, tab1, fft_size * sizeof(FFTSample));
                     r->rdft_calc(r, tab2);
@@ -421,6 +447,7 @@ int main(int argc, char **argv)
                     memcpy(tab2, tab1, fft_size * sizeof(FFTSample));
                     d->dct_calc(d, tab2);
                     break;
+#endif
                 }
             }
             duration = gettime() - time_start;
@@ -441,12 +468,14 @@ int main(int argc, char **argv)
     case TRANSFORM_FFT:
         ff_fft_end(s);
         break;
+#if CONFIG_FFT_FLOAT
     case TRANSFORM_RDFT:
         ff_rdft_end(r);
         break;
     case TRANSFORM_DCT:
         ff_dct_end(d);
         break;
+#endif
     }
 
     av_free(tab);