diff --git a/cinelerra-5.1/cinelerra/ffmpeg.C b/cinelerra-5.1/cinelerra/ffmpeg.C
index 3655d643..ba278378 100644
--- a/cinelerra-5.1/cinelerra/ffmpeg.C
+++ b/cinelerra-5.1/cinelerra/ffmpeg.C
@@ -381,7 +381,7 @@ AVHWDeviceType FFStream::decode_hw_activate()
 	return AV_HWDEVICE_TYPE_NONE;
 }
 
-int FFStream::decode_hw_format(AVCodec *decoder, AVHWDeviceType type)
+int FFStream::decode_hw_format(const AVCodec *decoder, AVHWDeviceType type)
 {
 	return 0;
 }
@@ -406,7 +406,7 @@ int FFStream::decode_activate()
 		}
 		while( ret >= 0 && st != 0 && !reading ) {
 			AVCodecID codec_id = st->codecpar->codec_id;
-			AVCodec *decoder = 0;
+			const AVCodec *decoder = 0;
 			if( is_video() ) {
 				if( ffmpeg->opt_video_decoder )
 					decoder = avcodec_find_decoder_by_name(ffmpeg->opt_video_decoder);
@@ -1850,7 +1850,7 @@ FFMPEG::~FFMPEG()
 	delete [] opt_hw_dev;
 }
 
-int FFMPEG::check_sample_rate(AVCodec *codec, int sample_rate)
+int FFMPEG::check_sample_rate(const AVCodec *codec, int sample_rate)
 {
 	const int *p = codec->supported_samplerates;
 	if( !p ) return sample_rate;
@@ -2100,7 +2100,7 @@ void FFMPEG::scan_audio_options(Asset *asset, EDL *edl)
 		cin_fmt = (int)av_get_sample_fmt(cin_sample_fmt);
 	if( cin_fmt < 0 ) {
 		char audio_codec[BCSTRLEN]; audio_codec[0] = 0;
-		AVCodec *av_codec = !FFMPEG::get_codec(audio_codec, "audio", asset->acodec) ?
+		const AVCodec *av_codec = !FFMPEG::get_codec(audio_codec, "audio", asset->acodec) ?
 			avcodec_find_encoder_by_name(audio_codec) : 0;
 		if( av_codec && av_codec->sample_fmts )
 			cin_fmt = find_best_sample_fmt_of_list(av_codec->sample_fmts, AV_SAMPLE_FMT_FLT);
@@ -2136,7 +2136,7 @@ void FFMPEG::scan_video_options(Asset *asset, EDL *edl)
 			cin_fmt = (int)av_get_pix_fmt(cin_pix_fmt);
 	if( cin_fmt < 0 ) {
 		char video_codec[BCSTRLEN];  video_codec[0] = 0;
-		AVCodec *av_codec = !get_codec(video_codec, "video", asset->vcodec) ?
+		const AVCodec *av_codec = !get_codec(video_codec, "video", asset->vcodec) ?
 			avcodec_find_encoder_by_name(video_codec) : 0;
 		if( av_codec && av_codec->pix_fmts ) {
 			if( 0 && edl ) { // frequently picks a bad answer
@@ -2331,9 +2331,9 @@ int FFCodecRemaps::add(const char *val)
 }
 
 
-int FFCodecRemaps::update(AVCodecID &codec_id, AVCodec *&decoder)
+int FFCodecRemaps::update(AVCodecID &codec_id, const AVCodec *&decoder)
 {
-	AVCodec *codec = avcodec_find_decoder(codec_id);
+	const AVCodec *codec = avcodec_find_decoder(codec_id);
 	if( !codec ) return -1;
 	const char *name = codec->name;
 	FFCodecRemaps &map = *this;
@@ -2553,7 +2553,7 @@ int FFMPEG::init_decoder(const char *filename)
 	char *sp = strrchr(bp, '.');
 	if( !sp ) sp = bp + strlen(bp);
 	FILE *fp = 0;
-	AVInputFormat *ifmt = 0;
+	const AVInputFormat *ifmt = 0;
 	if( sp ) {
 		strcpy(sp, ".opts");
 		fp = fopen(file_opts, "r");
@@ -2774,7 +2774,7 @@ int FFMPEG::open_encoder(const char *type, const char *spec)
 	AVCodecContext *ctx = 0;
 
 	const AVCodecDescriptor *codec_desc = 0;
-	AVCodec *codec = avcodec_find_encoder_by_name(codec_name);
+	const AVCodec *codec = avcodec_find_encoder_by_name(codec_name);
 	if( !codec ) {
 		eprintf(_("cant find codec %s:%s\n"), codec_name, filename);
 		ret = 1;
@@ -3672,7 +3672,7 @@ Preferences *FFMPEG::ff_prefs()
 
 double FFVideoStream::get_rotation_angle()
 {
-	int size = 0;
+	size_t size = 0;
 	int *matrix = (int*)av_stream_get_side_data(st, AV_PKT_DATA_DISPLAYMATRIX, &size);
 	int len = size/sizeof(*matrix);
 	if( !matrix || len < 5 ) return 0;
@@ -3897,7 +3897,7 @@ AVCodecContext *FFMPEG::activate_decoder(AVStream *st)
 	AVDictionary *copts = 0;
 	av_dict_copy(&copts, opts, 0);
 	AVCodecID codec_id = st->codecpar->codec_id;
-	AVCodec *decoder = 0;
+	const AVCodec *decoder = 0;
 	switch( st->codecpar->codec_type ) {
 	case AVMEDIA_TYPE_VIDEO:
 		if( opt_video_decoder )
diff --git a/cinelerra-5.1/cinelerra/ffmpeg.h b/cinelerra-5.1/cinelerra/ffmpeg.h
index 4f1624ce..6c7d68e0 100644
--- a/cinelerra-5.1/cinelerra/ffmpeg.h
+++ b/cinelerra-5.1/cinelerra/ffmpeg.h
@@ -25,6 +25,7 @@
 #include "vframe.inc"
 
 extern "C" {
+#include "libavcodec/bsf.h"
 #include "libavformat/avformat.h"
 #include "libavformat/avio.h"
 #include "libavcodec/avcodec.h"
@@ -86,7 +87,7 @@ public:
 	virtual int encode_activate();
 	virtual int decode_activate();
 	virtual AVHWDeviceType decode_hw_activate();
-	virtual int decode_hw_format(AVCodec *decoder, AVHWDeviceType type);
+	virtual int decode_hw_format(const AVCodec *decoder, AVHWDeviceType type);
 	virtual int write_packet(FFPacket &pkt);
 	int read_packet();
 	int seek(int64_t no, double rate);
@@ -290,7 +291,7 @@ class FFCodecRemaps : public ArrayList<FFCodecRemap>
 public:
 	FFCodecRemaps() {}
 	int add(const char *val);
-	int update(AVCodecID &codec_id, AVCodec *&decoder);
+	int update(AVCodecID &codec_id, const AVCodec *&decoder);
 };
 
 // for get_initial_timecode auto deletes
@@ -331,7 +332,7 @@ public:
 	static void ff_lock(const char *cp=0) { fflock.lock(cp); }
 	static void ff_unlock() { fflock.unlock(); }
 
-	int check_sample_rate(AVCodec *codec, int sample_rate);
+	int check_sample_rate(const AVCodec *codec, int sample_rate);
 	AVRational check_frame_rate(const AVRational *p, double frame_rate);
 	AVRational to_sample_aspect_ratio(Asset *asset);
 	AVRational to_time_base(int sample_rate);