[FFmpeg-devel] [PATCH] avcodec: add AVCODEC_REQUIRED_INPUT_BUFFER_PADDING_SIZE, split FF_INPUT_BUFFER_PADDING_SIZE

[wm4]

On Thu, 12 Jun 2014 23:06:13 +0200
Michael Niedermayer <michaelni at gmx.at> wrote:

> TODO bump minor version, update APIChanges
> 
> Signed-off-by: Michael Niedermayer <michaelni at gmx.at>
> ---
>  libavcodec/avcodec.h |   11 ++++++++++-
>  1 file changed, 10 insertions(+), 1 deletion(-)
> 
> diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
> index 68b1f26..ca66f3c 100644
> --- a/libavcodec/avcodec.h
> +++ b/libavcodec/avcodec.h
> @@ -608,13 +608,22 @@ typedef struct AVCodecDescriptor {
>  
>  /**
>   * @ingroup lavc_decoding
> + * The amount of padding that is allocated at the end of the input bitstream by
> + * libavformat and other libs, this affects all buffers which may reasonably be
> + * directly used as avcodec input buffers.
> + * The value of this symbol may be increased without major version bump.
> + */
> +#define FF_INPUT_BUFFER_PADDING_SIZE 32

Why is there something about libavformat and "other libs" in libavcodec?

The name of this define is more informative than these 4 lines of help
text.

> +
> +/**
> + * @ingroup lavc_decoding
>   * Required number of additionally allocated bytes at the end of the input bitstream for decoding.
>   * This is mainly needed because some optimized bitstream readers read
>   * 32 or 64 bit at once and could read over the end.<br>
>   * Note: If the first 23 bits of the additional bytes are not 0, then damaged
>   * MPEG bitstreams could cause overread and segfault.
>   */
> -#define FF_INPUT_BUFFER_PADDING_SIZE 32
> +#define AVCODEC_REQUIRED_INPUT_BUFFER_PADDING_SIZE 16

I don't understand the difference between these two.

>  
>  /**
>   * @ingroup lavc_encoding