1 files changed, 54 insertions, 0 deletions
diff --git a/libavcodec/tests/iirfilter.c b/libavcodec/tests/iirfilter.c
new file mode 100644
index 0000000000..a6001a3270
--- /dev/null
+++ b/libavcodec/tests/iirfilter.c
@@ -0,0 +1,54 @@
+/*
+ * 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
+ */
+
+#include <math.h>
+#include <stdint.h>
+#include <stdio.h>
+
+#include "libavutil/libm.h"
+
+#include "libavcodec/iirfilter.h"
+
+#define FILT_ORDER 4
+#define SIZE 1024
+
+int main(void)
+{
+    struct FFIIRFilterCoeffs *fcoeffs = NULL;
+    struct FFIIRFilterState  *fstate  = NULL;
+    float cutoff_coeff = 0.4;
+    int16_t x[SIZE], y[SIZE];
+    int i;
+
+    fcoeffs = ff_iir_filter_init_coeffs(NULL, FF_FILTER_TYPE_BUTTERWORTH,
+                                        FF_FILTER_MODE_LOWPASS, FILT_ORDER,
+                                        cutoff_coeff, 0.0, 0.0);
+    fstate  = ff_iir_filter_init_state(FILT_ORDER);
+
+    for (i = 0; i < SIZE; i++)
+        x[i] = lrint(0.75 * INT16_MAX * sin(0.5 * M_PI * i * i / SIZE));
+
+    ff_iir_filter(fcoeffs, fstate, SIZE, x, 1, y, 1);
+
+    for (i = 0; i < SIZE; i++)
+        printf("%6d %6d\n", x[i], y[i]);
+
+    ff_iir_filter_free_coeffs(fcoeffs);
+    ff_iir_filter_free_state(fstate);
+    return 0;
+}