[FFmpeg-devel] [PATCH 1/4] lavf/mpegts: drop a cargo-culted check

[FFmpeg-devel] [PATCH 1/4] lavf/mpegts: drop a cargo-culted check

[Anton Khirnov]

This check has survived the transition to AVCodecParameters, but is no
longer relevant after it, since the codec context is no longer updated
or accessed at all from the demuxer.
---
 libavformat/mpegts.c | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/libavformat/mpegts.c b/libavformat/mpegts.c
index bef00c88e7..1cf390e98e 100644
--- a/libavformat/mpegts.c
+++ b/libavformat/mpegts.c
@@ -919,11 +919,6 @@ static int mpegts_set_stream_info(AVStream *st, PESContext *pes,
     int old_codec_id   = st->codecpar->codec_id;
     int old_codec_tag  = st->codecpar->codec_tag;
 
-    if (avcodec_is_open(sti->avctx)) {
-        av_log(pes->stream, AV_LOG_DEBUG, "cannot set stream info, internal codec is open\n");
-        return 0;
-    }
-
     avpriv_set_pts_info(st, 33, 1, 90000);
     st->priv_data         = pes;
     st->codecpar->codec_type = AVMEDIA_TYPE_DATA;
-- 
2.42.0

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[FFmpeg-devel] [PATCH 2/4] lavf/flacdec: stop accessing FFStream.avctx

[Anton Khirnov]

The demuxer opens an internal parser instance in read_timestamp(), which
requires a codec context. There is no need for it to access the FFStream
one which is used for other purposes, it can allocate its own internal
one.
---
 libavformat/flacdec.c | 25 ++++++++++++++++++++++++-
 1 file changed, 24 insertions(+), 1 deletion(-)

diff --git a/libavformat/flacdec.c b/libavformat/flacdec.c
index ab9ef052f9..bbb205078a 100644
--- a/libavformat/flacdec.c
+++ b/libavformat/flacdec.c
@@ -36,6 +36,8 @@
 typedef struct FLACDecContext {
     FFRawDemuxerContext rawctx;
     int found_seektable;
+
+    AVCodecContext *parser_dec;
 } FLACDecContext;
 
 static void reset_index_position(int64_t metadata_head_size, AVStream *st)
@@ -269,6 +271,7 @@ static int flac_probe(const AVProbeData *p)
 static av_unused int64_t flac_read_timestamp(AVFormatContext *s, int stream_index,
                                              int64_t *ppos, int64_t pos_limit)
 {
+    FLACDecContext *flac = s->priv_data;
     FFFormatContext *const si = ffformatcontext(s);
     AVPacket *const pkt = si->parse_pkt;
     AVStream *st = s->streams[stream_index];
@@ -285,6 +288,16 @@ static av_unused int64_t flac_read_timestamp(AVFormatContext *s, int stream_inde
     }
     parser->flags |= PARSER_FLAG_USE_CODEC_TS;
 
+    if (!flac->parser_dec) {
+        flac->parser_dec = avcodec_alloc_context3(NULL);
+        if (!flac->parser_dec)
+            return AV_NOPTS_VALUE;
+
+        ret = avcodec_parameters_to_context(flac->parser_dec, st->codecpar);
+        if (ret < 0)
+            return ret;
+    }
+
     for (;;){
         uint8_t *data;
         int size;
@@ -298,7 +311,7 @@ static av_unused int64_t flac_read_timestamp(AVFormatContext *s, int stream_inde
                 av_assert1(!pkt->size);
             }
         }
-        av_parser_parse2(parser, ffstream(st)->avctx,
+        av_parser_parse2(parser, flac->parser_dec,
                          &data, &size, pkt->data, pkt->size,
                          pkt->pts, pkt->dts, *ppos);
 
@@ -318,6 +331,15 @@ static av_unused int64_t flac_read_timestamp(AVFormatContext *s, int stream_inde
     return pts;
 }
 
+static int flac_close(AVFormatContext *s)
+{
+    FLACDecContext *flac = s->priv_data;
+
+    avcodec_free_context(&flac->parser_dec);
+
+    return 0;
+}
+
 static int flac_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags) {
     AVStream *const st  = s->streams[0];
     FFStream *const sti = ffstream(st);
@@ -347,6 +369,7 @@ const AVInputFormat ff_flac_demuxer = {
     .long_name      = NULL_IF_CONFIG_SMALL("raw FLAC"),
     .read_probe     = flac_probe,
     .read_header    = flac_read_header,
+    .read_close     = flac_close,
     .read_packet    = ff_raw_read_partial_packet,
     .read_seek      = flac_seek,
     .read_timestamp = flac_read_timestamp,
-- 
2.42.0

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[FFmpeg-devel] [PATCH 3/4] lavf/demux: stop calling avcodec_close()

[Anton Khirnov]

Replace it with recreating the codec context.

This is the last remaining blocker for deprecating avcodec_close().
---
 libavformat/demux.c | 53 ++++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 48 insertions(+), 5 deletions(-)

diff --git a/libavformat/demux.c b/libavformat/demux.c
index 6f640b92b1..c1640c459c 100644
--- a/libavformat/demux.c
+++ b/libavformat/demux.c
@@ -1250,6 +1250,52 @@ static int64_t ts_to_samples(AVStream *st, int64_t ts)
     return av_rescale(ts, st->time_base.num * st->codecpar->sample_rate, st->time_base.den);
 }
 
+static int codec_close(FFStream *sti)
+{
+    AVCodecContext *avctx_new = NULL;
+    AVCodecParameters *par_tmp = NULL;
+    int ret = 0;
+
+    avctx_new = avcodec_alloc_context3(sti->avctx->codec);
+    if (!avctx_new) {
+        ret = AVERROR(ENOMEM);
+        goto fail;
+    }
+
+    par_tmp = avcodec_parameters_alloc();
+    if (!par_tmp) {
+        ret = AVERROR(ENOMEM);
+        goto fail;
+    }
+
+    ret = avcodec_parameters_from_context(par_tmp, sti->avctx);
+    if (ret < 0)
+        goto fail;
+
+    ret = avcodec_parameters_to_context(avctx_new, par_tmp);
+    if (ret < 0)
+        goto fail;
+
+    avctx_new->pkt_timebase = sti->avctx->pkt_timebase;
+
+#if FF_API_TICKS_PER_FRAME
+FF_DISABLE_DEPRECATION_WARNINGS
+    avctx_new->ticks_per_frame = sti->avctx->ticks_per_frame;
+FF_ENABLE_DEPRECATION_WARNINGS
+#endif
+
+    avcodec_free_context(&sti->avctx);
+    sti->avctx = avctx_new;
+
+    avctx_new = NULL;
+
+fail:
+    avcodec_free_context(&avctx_new);
+    avcodec_parameters_free(&par_tmp);
+
+    return ret;
+}
+
 static int read_frame_internal(AVFormatContext *s, AVPacket *pkt)
 {
     FFFormatContext *const si = ffformatcontext(s);
@@ -1286,7 +1332,7 @@ static int read_frame_internal(AVFormatContext *s, AVPacket *pkt)
         if (sti->need_context_update) {
             if (avcodec_is_open(sti->avctx)) {
                 av_log(s, AV_LOG_DEBUG, "Demuxer context update while decoder is open, closing and trying to re-open\n");
-                avcodec_close(sti->avctx);
+                codec_close(sti);
                 sti->info->found_decoder = 0;
             }
 
@@ -3017,10 +3063,7 @@ find_stream_info_err:
             av_freep(&sti->info->duration_error);
             av_freep(&sti->info);
         }
-        avcodec_close(sti->avctx);
-        // FIXME: avcodec_close() frees AVOption settable fields which includes ch_layout,
-        //        so we need to restore it.
-        av_channel_layout_copy(&sti->avctx->ch_layout, &st->codecpar->ch_layout);
+        codec_close(sti);
         av_bsf_free(&sti->extract_extradata.bsf);
     }
     if (ic->pb) {
-- 
2.42.0

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[FFmpeg-devel] [PATCH 4/4] lavc: deprecate avcodec_close()

[Anton Khirnov]

Its use has been discouraged since 2016, but now is no longer used in
avformat, so there is no reason to keep it public.
---
 libavcodec/avcodec.c              | 12 +++++++++---
 libavcodec/avcodec.h              |  5 ++++-
 libavcodec/avcodec_internal.h     |  2 ++
 libavcodec/frame_thread_encoder.c |  5 +++--
 libavcodec/options.c              |  3 ++-
 libavcodec/version_major.h        |  1 +
 6 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/libavcodec/avcodec.c b/libavcodec/avcodec.c
index a6c8629f6c..b6d27ada21 100644
--- a/libavcodec/avcodec.c
+++ b/libavcodec/avcodec.c
@@ -377,7 +377,7 @@ end:
 
     return ret;
 free_and_end:
-    avcodec_close(avctx);
+    ff_codec_close(avctx);
     goto end;
 }
 
@@ -432,12 +432,12 @@ void avsubtitle_free(AVSubtitle *sub)
     memset(sub, 0, sizeof(*sub));
 }
 
-av_cold int avcodec_close(AVCodecContext *avctx)
+av_cold void ff_codec_close(AVCodecContext *avctx)
 {
     int i;
 
     if (!avctx)
-        return 0;
+        return;
 
     if (avcodec_is_open(avctx)) {
         AVCodecInternal *avci = avctx->internal;
@@ -497,9 +497,15 @@ av_cold int avcodec_close(AVCodecContext *avctx)
 
     avctx->codec = NULL;
     avctx->active_thread_type = 0;
+}
 
+#if FF_API_AVCODEC_CLOSE
+int avcodec_close(AVCodecContext *avctx)
+{
+    ff_codec_close(avctx);
     return 0;
 }
+#endif
 
 static const char *unknown_if_null(const char *str)
 {
diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index 7fb44e28f4..0018ccbb0c 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -2411,6 +2411,7 @@ int avcodec_parameters_to_context(AVCodecContext *codec,
  */
 int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
 
+#if FF_API_AVCODEC_CLOSE
 /**
  * Close a given AVCodecContext and free all the data associated with it
  * (but not the AVCodecContext itself).
@@ -2419,12 +2420,14 @@ int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **op
  * the codec-specific data allocated in avcodec_alloc_context3() with a non-NULL
  * codec. Subsequent calls will do nothing.
  *
- * @note Do not use this function. Use avcodec_free_context() to destroy a
+ * @deprecated Do not use this function. Use avcodec_free_context() to destroy a
  * codec context (either open or closed). Opening and closing a codec context
  * multiple times is not supported anymore -- use multiple codec contexts
  * instead.
  */
+attribute_deprecated
 int avcodec_close(AVCodecContext *avctx);
+#endif
 
 /**
  * Free all allocated data in the given subtitle struct.
diff --git a/libavcodec/avcodec_internal.h b/libavcodec/avcodec_internal.h
index 9b93ff3d81..4d1cb3a314 100644
--- a/libavcodec/avcodec_internal.h
+++ b/libavcodec/avcodec_internal.h
@@ -56,4 +56,6 @@ void ff_encode_flush_buffers(struct AVCodecContext *avctx);
 struct AVCodecInternal *ff_decode_internal_alloc(void);
 struct AVCodecInternal *ff_encode_internal_alloc(void);
 
+void ff_codec_close(struct AVCodecContext *avctx);
+
 #endif // AVCODEC_AVCODEC_INTERNAL_H
diff --git a/libavcodec/frame_thread_encoder.c b/libavcodec/frame_thread_encoder.c
index 62d9580ad4..cda5158117 100644
--- a/libavcodec/frame_thread_encoder.c
+++ b/libavcodec/frame_thread_encoder.c
@@ -27,6 +27,7 @@
 #include "libavutil/opt.h"
 #include "libavutil/thread.h"
 #include "avcodec.h"
+#include "avcodec_internal.h"
 #include "encode.h"
 #include "internal.h"
 #include "pthread_internal.h"
@@ -110,7 +111,7 @@ static void * attribute_align_arg worker(void *v){
         pthread_mutex_unlock(&c->finished_task_mutex);
     }
 end:
-    avcodec_close(avctx);
+    ff_codec_close(avctx);
     av_freep(&avctx);
     return NULL;
 }
@@ -230,7 +231,7 @@ av_cold int ff_frame_thread_encoder_init(AVCodecContext *avctx)
 
     return 0;
 fail:
-    avcodec_close(thread_avctx);
+    ff_codec_close(thread_avctx);
     av_freep(&thread_avctx);
     avctx->thread_count = i;
     av_log(avctx, AV_LOG_ERROR, "ff_frame_thread_encoder_init failed\n");
diff --git a/libavcodec/options.c b/libavcodec/options.c
index a9b35ee1c3..05a355fb45 100644
--- a/libavcodec/options.c
+++ b/libavcodec/options.c
@@ -27,6 +27,7 @@
 #include "config_components.h"
 
 #include "avcodec.h"
+#include "avcodec_internal.h"
 #include "codec_internal.h"
 #include "libavutil/avassert.h"
 #include "libavutil/internal.h"
@@ -172,7 +173,7 @@ void avcodec_free_context(AVCodecContext **pavctx)
     if (!avctx)
         return;
 
-    avcodec_close(avctx);
+    ff_codec_close(avctx);
 
     av_freep(&avctx->extradata);
     av_freep(&avctx->subtitle_header);
diff --git a/libavcodec/version_major.h b/libavcodec/version_major.h
index b9164fe5c6..45209c0a4f 100644
--- a/libavcodec/version_major.h
+++ b/libavcodec/version_major.h
@@ -52,6 +52,7 @@
 
 #define FF_API_AVFFT               (LIBAVCODEC_VERSION_MAJOR < 62)
 #define FF_API_FF_PROFILE_LEVEL    (LIBAVCODEC_VERSION_MAJOR < 62)
+#define FF_API_AVCODEC_CLOSE       (LIBAVCODEC_VERSION_MAJOR < 62)
 
 // reminder to remove CrystalHD decoders on next major bump
 #define FF_CODEC_CRYSTAL_HD        (LIBAVCODEC_VERSION_MAJOR < 61)
-- 
2.42.0

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Re: [FFmpeg-devel] [PATCH 3/4] lavf/demux: stop calling avcodec_close()

[Leo Izen]

[-- Attachment #1.1.1: Type: text/plain, Size: 3184 bytes --]

On 2/1/24 03:29, Anton Khirnov wrote:
> Replace it with recreating the codec context.
> 
> This is the last remaining blocker for deprecating avcodec_close().
> ---
>   libavformat/demux.c | 53 ++++++++++++++++++++++++++++++++++++++++-----
>   1 file changed, 48 insertions(+), 5 deletions(-)
> 
> diff --git a/libavformat/demux.c b/libavformat/demux.c
> index 6f640b92b1..c1640c459c 100644
> --- a/libavformat/demux.c
> +++ b/libavformat/demux.c
> @@ -1250,6 +1250,52 @@ static int64_t ts_to_samples(AVStream *st, int64_t ts)
>       return av_rescale(ts, st->time_base.num * st->codecpar->sample_rate, st->time_base.den);
>   }
>   
> +static int codec_close(FFStream *sti)
> +{
> +    AVCodecContext *avctx_new = NULL;
> +    AVCodecParameters *par_tmp = NULL;
> +    int ret = 0;
> +

I believe we can drop the initialization from avctx_new and from ret, 
because avctx_new is assigned immediately, and ret is assigned before 
each goto before it's assigned properly.


> +    avctx_new = avcodec_alloc_context3(sti->avctx->codec);
> +    if (!avctx_new) {
> +        ret = AVERROR(ENOMEM);
> +        goto fail;
> +    }
> +
> +    par_tmp = avcodec_parameters_alloc();
> +    if (!par_tmp) {
> +        ret = AVERROR(ENOMEM);
> +        goto fail;
> +    }
> +
> +    ret = avcodec_parameters_from_context(par_tmp, sti->avctx);
> +    if (ret < 0)
> +        goto fail;
> +
> +    ret = avcodec_parameters_to_context(avctx_new, par_tmp);
> +    if (ret < 0)
> +        goto fail;
> +
> +    avctx_new->pkt_timebase = sti->avctx->pkt_timebase;
> +
> +#if FF_API_TICKS_PER_FRAME
> +FF_DISABLE_DEPRECATION_WARNINGS
> +    avctx_new->ticks_per_frame = sti->avctx->ticks_per_frame;
> +FF_ENABLE_DEPRECATION_WARNINGS
> +#endif
> +
> +    avcodec_free_context(&sti->avctx);
> +    sti->avctx = avctx_new;
> +
> +    avctx_new = NULL;
> +
> +fail:
> +    avcodec_free_context(&avctx_new);
> +    avcodec_parameters_free(&par_tmp);
> +
> +    return ret;
> +}
> +
>   static int read_frame_internal(AVFormatContext *s, AVPacket *pkt)
>   {
>       FFFormatContext *const si = ffformatcontext(s);
> @@ -1286,7 +1332,7 @@ static int read_frame_internal(AVFormatContext *s, AVPacket *pkt)
>           if (sti->need_context_update) {
>               if (avcodec_is_open(sti->avctx)) {
>                   av_log(s, AV_LOG_DEBUG, "Demuxer context update while decoder is open, closing and trying to re-open\n");
> -                avcodec_close(sti->avctx);
> +                codec_close(sti);
>                   sti->info->found_decoder = 0;
>               }
>   
> @@ -3017,10 +3063,7 @@ find_stream_info_err:
>               av_freep(&sti->info->duration_error);
>               av_freep(&sti->info);
>           }
> -        avcodec_close(sti->avctx);
> -        // FIXME: avcodec_close() frees AVOption settable fields which includes ch_layout,
> -        //        so we need to restore it.
> -        av_channel_layout_copy(&sti->avctx->ch_layout, &st->codecpar->ch_layout);
> +        codec_close(sti);
>           av_bsf_free(&sti->extract_extradata.bsf);
>       }
>       if (ic->pb) {

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Re: [FFmpeg-devel] [PATCH 3/4] lavf/demux: stop calling avcodec_close()

[James Almer]

On 2/1/2024 5:29 AM, Anton Khirnov wrote:
> Replace it with recreating the codec context.
> 
> This is the last remaining blocker for deprecating avcodec_close().
> ---
>   libavformat/demux.c | 53 ++++++++++++++++++++++++++++++++++++++++-----
>   1 file changed, 48 insertions(+), 5 deletions(-)
> 
> diff --git a/libavformat/demux.c b/libavformat/demux.c
> index 6f640b92b1..c1640c459c 100644
> --- a/libavformat/demux.c
> +++ b/libavformat/demux.c
> @@ -1250,6 +1250,52 @@ static int64_t ts_to_samples(AVStream *st, int64_t ts)
>       return av_rescale(ts, st->time_base.num * st->codecpar->sample_rate, st->time_base.den);
>   }
>   
> +static int codec_close(FFStream *sti)

This returns an error code but you're not checking it.

> +{
> +    AVCodecContext *avctx_new = NULL;
> +    AVCodecParameters *par_tmp = NULL;
> +    int ret = 0;
> +
> +    avctx_new = avcodec_alloc_context3(sti->avctx->codec);
> +    if (!avctx_new) {
> +        ret = AVERROR(ENOMEM);
> +        goto fail;
> +    }
> +
> +    par_tmp = avcodec_parameters_alloc();
> +    if (!par_tmp) {
> +        ret = AVERROR(ENOMEM);
> +        goto fail;
> +    }
> +
> +    ret = avcodec_parameters_from_context(par_tmp, sti->avctx);
> +    if (ret < 0)
> +        goto fail;
> +
> +    ret = avcodec_parameters_to_context(avctx_new, par_tmp);
> +    if (ret < 0)
> +        goto fail;
> +
> +    avctx_new->pkt_timebase = sti->avctx->pkt_timebase;
> +
> +#if FF_API_TICKS_PER_FRAME
> +FF_DISABLE_DEPRECATION_WARNINGS
> +    avctx_new->ticks_per_frame = sti->avctx->ticks_per_frame;
> +FF_ENABLE_DEPRECATION_WARNINGS
> +#endif
> +
> +    avcodec_free_context(&sti->avctx);
> +    sti->avctx = avctx_new;
> +
> +    avctx_new = NULL;
> +
> +fail:
> +    avcodec_free_context(&avctx_new);
> +    avcodec_parameters_free(&par_tmp);
> +
> +    return ret;

For success scenarios, this will return whatever was last set on ret, 
which in this case is the return value of 
avcodec_parameters_to_context() that just happens to be 0. But something 
else could be added later that also sets ret after it, so the proper 
thing to do is to set ret to 0 immediately above the fail label.

> +}
> +
>   static int read_frame_internal(AVFormatContext *s, AVPacket *pkt)
>   {
>       FFFormatContext *const si = ffformatcontext(s);
> @@ -1286,7 +1332,7 @@ static int read_frame_internal(AVFormatContext *s, AVPacket *pkt)
>           if (sti->need_context_update) {
>               if (avcodec_is_open(sti->avctx)) {
>                   av_log(s, AV_LOG_DEBUG, "Demuxer context update while decoder is open, closing and trying to re-open\n");
> -                avcodec_close(sti->avctx);
> +                codec_close(sti);
>                   sti->info->found_decoder = 0;
>               }
>   
> @@ -3017,10 +3063,7 @@ find_stream_info_err:
>               av_freep(&sti->info->duration_error);
>               av_freep(&sti->info);
>           }
> -        avcodec_close(sti->avctx);
> -        // FIXME: avcodec_close() frees AVOption settable fields which includes ch_layout,
> -        //        so we need to restore it.
> -        av_channel_layout_copy(&sti->avctx->ch_layout, &st->codecpar->ch_layout);
> +        codec_close(sti);
>           av_bsf_free(&sti->extract_extradata.bsf);
>       }
>       if (ic->pb) {
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Re: [FFmpeg-devel] [PATCH 3/4] lavf/demux: stop calling avcodec_close()

[Anton Khirnov]

Quoting Leo Izen (2024-02-03 03:35:45)
> On 2/1/24 03:29, Anton Khirnov wrote:
> > Replace it with recreating the codec context.
> > 
> > This is the last remaining blocker for deprecating avcodec_close().
> > ---
> >   libavformat/demux.c | 53 ++++++++++++++++++++++++++++++++++++++++-----
> >   1 file changed, 48 insertions(+), 5 deletions(-)
> > 
> > diff --git a/libavformat/demux.c b/libavformat/demux.c
> > index 6f640b92b1..c1640c459c 100644
> > --- a/libavformat/demux.c
> > +++ b/libavformat/demux.c
> > @@ -1250,6 +1250,52 @@ static int64_t ts_to_samples(AVStream *st, int64_t ts)
> >       return av_rescale(ts, st->time_base.num * st->codecpar->sample_rate, st->time_base.den);
> >   }
> >   
> > +static int codec_close(FFStream *sti)
> > +{
> > +    AVCodecContext *avctx_new = NULL;
> > +    AVCodecParameters *par_tmp = NULL;
> > +    int ret = 0;
> > +
> 
> I believe we can drop the initialization from avctx_new and from ret, 
> because avctx_new is assigned immediately, and ret is assigned before 
> each goto before it's assigned properly.

It's safer wrt future modifications of the code, e.g. if someone would
insert something that could fail before allocating avctx.

-- 
Anton Khirnov
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[FFmpeg-devel] [PATCH v2 3/4] lavf/demux: stop calling avcodec_close()

[Anton Khirnov]

Replace it with recreating the codec context.

This is the last remaining blocker for deprecating avcodec_close().
---
Applied review comments.
---
 libavformat/demux.c | 61 +++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 56 insertions(+), 5 deletions(-)

diff --git a/libavformat/demux.c b/libavformat/demux.c
index 6f640b92b1..b70979c520 100644
--- a/libavformat/demux.c
+++ b/libavformat/demux.c
@@ -1250,6 +1250,53 @@ static int64_t ts_to_samples(AVStream *st, int64_t ts)
     return av_rescale(ts, st->time_base.num * st->codecpar->sample_rate, st->time_base.den);
 }
 
+static int codec_close(FFStream *sti)
+{
+    AVCodecContext *avctx_new = NULL;
+    AVCodecParameters *par_tmp = NULL;
+    int ret;
+
+    avctx_new = avcodec_alloc_context3(sti->avctx->codec);
+    if (!avctx_new) {
+        ret = AVERROR(ENOMEM);
+        goto fail;
+    }
+
+    par_tmp = avcodec_parameters_alloc();
+    if (!par_tmp) {
+        ret = AVERROR(ENOMEM);
+        goto fail;
+    }
+
+    ret = avcodec_parameters_from_context(par_tmp, sti->avctx);
+    if (ret < 0)
+        goto fail;
+
+    ret = avcodec_parameters_to_context(avctx_new, par_tmp);
+    if (ret < 0)
+        goto fail;
+
+    avctx_new->pkt_timebase = sti->avctx->pkt_timebase;
+
+#if FF_API_TICKS_PER_FRAME
+FF_DISABLE_DEPRECATION_WARNINGS
+    avctx_new->ticks_per_frame = sti->avctx->ticks_per_frame;
+FF_ENABLE_DEPRECATION_WARNINGS
+#endif
+
+    avcodec_free_context(&sti->avctx);
+    sti->avctx = avctx_new;
+
+    avctx_new = NULL;
+    ret       = 0;
+
+fail:
+    avcodec_free_context(&avctx_new);
+    avcodec_parameters_free(&par_tmp);
+
+    return ret;
+}
+
 static int read_frame_internal(AVFormatContext *s, AVPacket *pkt)
 {
     FFFormatContext *const si = ffformatcontext(s);
@@ -1286,8 +1333,10 @@ static int read_frame_internal(AVFormatContext *s, AVPacket *pkt)
         if (sti->need_context_update) {
             if (avcodec_is_open(sti->avctx)) {
                 av_log(s, AV_LOG_DEBUG, "Demuxer context update while decoder is open, closing and trying to re-open\n");
-                avcodec_close(sti->avctx);
+                ret = codec_close(sti);
                 sti->info->found_decoder = 0;
+                if (ret < 0)
+                    return ret;
             }
 
             /* close parser, because it depends on the codec */
@@ -3013,14 +3062,16 @@ find_stream_info_err:
     for (unsigned i = 0; i < ic->nb_streams; i++) {
         AVStream *const st  = ic->streams[i];
         FFStream *const sti = ffstream(st);
+        int err;
+
         if (sti->info) {
             av_freep(&sti->info->duration_error);
             av_freep(&sti->info);
         }
-        avcodec_close(sti->avctx);
-        // FIXME: avcodec_close() frees AVOption settable fields which includes ch_layout,
-        //        so we need to restore it.
-        av_channel_layout_copy(&sti->avctx->ch_layout, &st->codecpar->ch_layout);
+
+        err = codec_close(sti);
+        if (err < 0 && ret >= 0)
+            ret = err;
         av_bsf_free(&sti->extract_extradata.bsf);
     }
     if (ic->pb) {
-- 
2.42.0

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