diff --git a/src/codec/audio/AudioDecoder.cpp b/src/codec/audio/AudioDecoder.cpp
index 52a13970..3947a38b 100644
--- a/src/codec/audio/AudioDecoder.cpp
+++ b/src/codec/audio/AudioDecoder.cpp
@@ -76,7 +76,8 @@ bool AudioDecoder::decode(const Packet &packet)
     if (!isAvailable())
         return false;
     DPTR_D(AudioDecoder);
-    int ret = avcodec_decode_audio4(d.codec_ctx, d.frame, &d.got_frame_ptr, packet.asAVPacket());
+    // const AVPacket*: ffmpeg >= 1.0. no libav
+    int ret = avcodec_decode_audio4(d.codec_ctx, d.frame, &d.got_frame_ptr, (AVPacket*)packet.asAVPacket());
     d.undecoded_size = qMin(packet.data.size() - ret, packet.data.size());
     if (ret == AVERROR(EAGAIN)) {
         return false;
diff --git a/src/codec/video/VideoDecoder.cpp b/src/codec/video/VideoDecoder.cpp
index 948144bb..b30e74a1 100644
--- a/src/codec/video/VideoDecoder.cpp
+++ b/src/codec/video/VideoDecoder.cpp
@@ -127,7 +127,8 @@ bool VideoDecoder::decode(const Packet &packet)
         return false;
     DPTR_D(VideoDecoder);
     // some decoders might in addition need other fields like flags&AV_PKT_FLAG_KEY
-    int ret = avcodec_decode_video2(d.codec_ctx, d.frame, &d.got_frame_ptr, packet.asAVPacket());
+    // const AVPacket*: ffmpeg >= 1.0. no libav
+    int ret = avcodec_decode_video2(d.codec_ctx, d.frame, &d.got_frame_ptr, (AVPacket*)packet.asAVPacket());
     //qDebug("pic_type=%c", av_get_picture_type_char(d.frame->pict_type));
     d.undecoded_size = qMin(packet.data.size() - ret, packet.data.size());
     if (ret < 0) {