[FFmpeg-devel] [PATCH] avcodec_copy_context()

[Michael Niedermayer]

On Tue, Mar 30, 2010 at 02:23:03PM -0400, Ronald S. Bultje wrote:
> Hi,
> 
> 2010/3/30 M?ns Rullg?rd <mans at mansr.com>:
> > Stefano Sabatini <stefano.sabatini-lala at poste.it> writes:
> >> On date Tuesday 2010-03-30 10:22:26 -0400, Ronald S. Bultje encoded:
> >>> + * Copy the settings of the source AVCodecContext into the destination
> >>
> >> Nit: "Copies" (but I won't fight the Third Person Holy War so do as
> >> you prefer).
> 
> This will get so funny. ;-). Left as is for now, I don't think it matters.
> 
> >>> + * AVCodecContext. The resulting destination codec context will be
> >>> + * unopened, i.e. you are required to call avcodec_open() before you
> >>> + * can use this AVCodecContext to decode/encode video/audio data.
> >>> + *
> >>> + * @param dest target codec context, should be initialized with
> >>> + * ? ? ? ? ? ? #avcodec_alloc_context(), but otherwise uninitialized
> >>> + * @param src source codec context
> >>> + * @returns AVERROR() on error (e.g. memory allocation error), 0 on success.
> >>
> >> The final "." is not required.
> >
> > @return
> 
> Both fixed.
> 
> Ronald

>  avcodec.h |   13 +++++++++++++
>  options.c |   52 ++++++++++++++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 65 insertions(+)
> e20e4b0904567737a11dc454a20f4c823ae17de7  avcodec_copy_context.patch
> Index: ffmpeg-svn/libavcodec/avcodec.h
> ===================================================================
> --- ffmpeg-svn.orig/libavcodec/avcodec.h	2010-03-29 13:37:31.000000000 -0400
> +++ ffmpeg-svn/libavcodec/avcodec.h	2010-03-30 12:00:24.000000000 -0400
> @@ -3256,6 +3256,19 @@
>  AVCodecContext *avcodec_alloc_context2(enum CodecType);
>  
>  /**
> + * Copy the settings of the source AVCodecContext into the destination
> + * AVCodecContext. The resulting destination codec context will be
> + * unopened, i.e. you are required to call avcodec_open() before you
> + * can use this AVCodecContext to decode/encode video/audio data.
> + *

> + * @param dest target codec context, should be allocated with
> + *             #avcodec_alloc_context(), but otherwise uninitialized

this should be checked if(->codec) or so maybe


> + * @param src source codec context
> + * @return AVERROR() on error (e.g. memory allocation error), 0 on success
> + */
> +int avcodec_copy_context(AVCodecContext *dest, const AVCodecContext *src);
> +
> +/**
>   * Sets the fields of the given AVFrame to default values.
>   *
>   * @param pic The AVFrame of which the fields should be set to default values.
> Index: ffmpeg-svn/libavcodec/options.c
> ===================================================================
> --- ffmpeg-svn.orig/libavcodec/options.c	2010-03-29 13:37:31.000000000 -0400
> +++ ffmpeg-svn/libavcodec/options.c	2010-03-29 13:37:49.000000000 -0400
> @@ -471,3 +471,55 @@
>      return avcodec_alloc_context2(CODEC_TYPE_UNKNOWN);
>  }
>  
> +int avcodec_copy_context(AVCodecContext *dest, const AVCodecContext *src)
> +{
> +    memcpy(dest, src, sizeof(*dest));
> +
> +    /* set values specific to opened codecs back to their default state */
> +    dest->priv_data       = NULL;
> +    dest->codec           = NULL;
> +    dest->palctrl         = NULL;
> +    dest->slice_offset    = NULL;
> +    dest->internal_buffer = NULL;
> +    dest->hwaccel         = NULL;
> +    dest->execute         = NULL;
> +    dest->execute2        = NULL;
> +    dest->reget_buffer    = NULL;
> +    dest->thread_opaque   = NULL;
> +
> +    /* reallocate values that should be allocated separately */
> +    if (dest->rc_eq) {
> +        dest->rc_eq = av_strdup(src->rc_eq);
> +        if (!dest->rc_eq)
> +            return AVERROR(ENOMEM);
> +    }
> +    if (src->extradata && src->extradata_size > 0) {
> +        dest->extradata = av_malloc(src->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
> +        if (!dest->extradata)
> +            return AVERROR(ENOMEM);
> +        memcpy(dest->extradata, src->extradata, src->extradata_size);
> +        memset(dest->extradata + dest->extradata_size, 0,
> +               FF_INPUT_BUFFER_PADDING_SIZE);
> +    }
> +    if (src->intra_matrix) {
> +        dest->intra_matrix = av_malloc(64 * sizeof(int16_t));
> +        if (!dest->intra_matrix)
> +            return AVERROR(ENOMEM);
> +        memcpy(dest->intra_matrix, src->intra_matrix, 64 * sizeof(int16_t));
> +    }
> +    if (src->inter_matrix) {
> +        dest->inter_matrix = av_malloc(64 * sizeof(int16_t));
> +        if (!dest->inter_matrix)
> +            return AVERROR(ENOMEM);
> +        memcpy(dest->inter_matrix, src->inter_matrix, 64 * sizeof(int16_t));
> +    }
> +    if (src->rc_override_count > 0 && src->rc_override) {
> +        dest->rc_override = av_malloc(sizeof(*src->rc_override) * src->rc_override_count);
> +        if (!dest->rc_override)
> +            return AVERROR(ENOMEM);
> +        memcpy(dest->rc_override, src->rc_override,
> +               dest->rc_override_count * sizeof(*src->rc_override));
> +    }

you might want to have a macro for the if(x) alloc,goto error,cpy


[...]
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Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

Many that live deserve death. And some that die deserve life. Can you give
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