1 files changed, 16 insertions, 5 deletions

diff --git a/libavcodec/noise_bsf.c b/libavcodec/noise_bsf.c
index 3b41dbf..84b9403 100644
--- a/libavcodec/noise_bsf.c
+++ b/libavcodec/noise_bsf.c
@@ -1,20 +1,20 @@
 /*
  * copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
  *
- * This file is part of Libav.
+ * This file is part of FFmpeg.
  *
- * Libav is free software; you can redistribute it and/or
+ * FFmpeg 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,
+ * FFmpeg 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
+ * License along with FFmpeg; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
@@ -31,6 +31,7 @@
 typedef struct NoiseContext {
     const AVClass *class;
     int amount;
+    int dropamount;
     unsigned int state;
 } NoiseContext;
 
@@ -41,10 +42,19 @@ static int noise(AVBSFContext *ctx, AVPacket *out)
     int amount = s->amount > 0 ? s->amount : (s->state % 10001 + 1);
     int i, ret = 0;
 
+    if (amount <= 0)
+        return AVERROR(EINVAL);
+
     ret = ff_bsf_get_packet(ctx, &in);
     if (ret < 0)
         return ret;
 
+    if (s->dropamount > 0 && s->state % s->dropamount == 0) {
+        s->state++;
+        av_packet_free(&in);
+        return AVERROR(EAGAIN);
+    }
+
     ret = av_new_packet(out, in->size);
     if (ret < 0)
         goto fail;
@@ -70,6 +80,7 @@ fail:
 #define OFFSET(x) offsetof(NoiseContext, x)
 static const AVOption options[] = {
     { "amount", NULL, OFFSET(amount), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX },
+    { "dropamount", NULL, OFFSET(dropamount), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX },
     { NULL },
 };
 
@@ -82,7 +93,7 @@ static const AVClass noise_class = {
 
 const AVBitStreamFilter ff_noise_bsf = {
     .name           = "noise",
-    .priv_data_size = sizeof(int),
+    .priv_data_size = sizeof(NoiseContext),
     .priv_class     = &noise_class,
     .filter         = noise,
 };