[FFmpeg-devel,v4,10/10] configure: add --enable-libvpl option

This allows user to build FFmpeg against Intel oneVPL. oneVPL 2.2
is the required minimum version when building Intel oneVPL code.

It will fail to run configure script if both libmfx and libvpl are
enabled.

It is recommended to use oneVPL for new work, even for currently available
hardwares [1]

[1] https://software.intel.com/content/www/us/en/develop/articles/upgrading-from-msdk-to-onevpl.html
---
 configure | 26 ++++++++++++++++++++------
 1 file changed, 20 insertions(+), 6 deletions(-)

On 9/23/2021 3:28 AM, Haihao Xiang wrote:
> This allows user to build FFmpeg against Intel oneVPL. oneVPL 2.2
> is the required minimum version when building Intel oneVPL code.
> 
> It will fail to run configure script if both libmfx and libvpl are
> enabled.
> 
> It is recommended to use oneVPL for new work, even for currently available
> hardwares [1]
> 
> [1] https://software.intel.com/content/www/us/en/develop/articles/upgrading-from-msdk-to-onevpl.html
> ---
>   configure | 26 ++++++++++++++++++++------
>   1 file changed, 20 insertions(+), 6 deletions(-)
> 
> diff --git a/configure b/configure
> index 9655a5823e..e9d2564819 100755
> --- a/configure
> +++ b/configure
> @@ -337,6 +337,7 @@ External library support:
>     --disable-ffnvcodec      disable dynamically linked Nvidia code [autodetect]
>     --enable-libdrm          enable DRM code (Linux) [no]
>     --enable-libmfx          enable Intel MediaSDK (AKA Quick Sync Video) code via libmfx [no]
> +  --enable-libvpl          enable Intel oneVPL code via libvpl if libmfx is not used [no]
>     --enable-libnpp          enable Nvidia Performance Primitives-based code [no]
>     --enable-mmal            enable Broadcom Multi-Media Abstraction Layer (Raspberry Pi) via MMAL [no]
>     --disable-nvdec          disable Nvidia video decoding acceleration (via hwaccel) [autodetect]
> @@ -1895,6 +1896,7 @@ HWACCEL_LIBRARY_NONFREE_LIST="
>   HWACCEL_LIBRARY_LIST="
>       $HWACCEL_LIBRARY_NONFREE_LIST
>       libmfx
> +    libvpl
>       mmal
>       omx
>       opencl
> @@ -6428,22 +6430,34 @@ enabled libilbc           && require libilbc ilbc.h WebRtcIlbcfix_InitDecode -li
>   enabled libklvanc         && require libklvanc libklvanc/vanc.h klvanc_context_create -lklvanc
>   enabled libkvazaar        && require_pkg_config libkvazaar "kvazaar >= 0.8.1" kvazaar.h kvz_api_get
>   enabled liblensfun        && require_pkg_config liblensfun lensfun lensfun.h lf_db_new
> +
> +if enabled libmfx && enabled libvpl; then
> +   die "ERROR: can not use libmfx and libvpl together"
>   # While it may appear that require is being used as a pkg-config
>   # fallback for libmfx, it is actually being used to detect a different
>   # installation route altogether.  If libmfx is installed via the Intel
>   # Media SDK or Intel Media Server Studio, these don't come with
>   # pkg-config support.  Instead, users should make sure that the build
>   # can find the libraries and headers through other means.
> -
> -enabled libmfx            && { { check_pkg_config libmfx "libmfx < 2.0" "mfxvideo.h" MFXInit ||
> +elif enabled libmfx; then

Instead of elif, maybe just do

if enabled libmfx && enabled libvpl; then
    die()
if enabled libmfx; then
    checks
if enabled enabled libvpl; then
    checks

> +    { check_pkg_config libmfx "libmfx < 2.0" "mfxvideo.h" MFXInit || \

Is this backslash needed?

>   # Some old versions of libmfx have the following settings in libmfx.pc:
>   #   includedir=/usr/include
>   #   Cflags: -I${includedir}
>   # So add -I${includedir}/mfx to CFLAGS
> -                                 { check_pkg_config libmfx "libmfx < 2.0" "mfx/mfxvideo.h" MFXInit && add_cflags -I$($pkg_config --variable=includedir libmfx)/mfx; } ||
> -                                 { require "libmfx < 2.0" "mfxvideo.h" MFXInit "-llibmfx $advapi32_extralibs" && warn "using libmfx without pkg-config"; } } &&
> -                               warn "build FFmpeg against libmfx 1.x, obsolete features of libmfx such as OPAQUE memory,\n"\
> -                                    "multi-frame encode, user plugins and LA_EXT rate control mode are enabled"; }
> +      { check_pkg_config libmfx "libmfx < 2.0" "mfx/mfxvideo.h" MFXInit && add_cflags -I$($pkg_config --variable=includedir libmfx)/mfx; } ||
> +      { require "libmfx < 2.0" "mfxvideo.h" MFXInit "-llibmfx $advapi32_extralibs" && warn "using libmfx without pkg-config"; } } &&
> +    warn "build FFmpeg against libmfx 1.x, obsolete features of libmfx such as OPAQUE memory,\n"\
> +         "multi-frame encode, user plugins and LA_EXT rate control mode are enabled"
> +elif enabled libvpl; then
> +# Consider pkg-config only. The name of libmfx is still used in the following check for --enable-libvpl option
> +# because QSV has dependency on libmfx, we can use the same dependency if using libmfx in this check.
> +    check_pkg_config libmfx "vpl >= 2.2" "mfxvideo.h mfxdispatcher.h" MFXLoad && \
> +        warn "build FFmpeg against oneVPL 2.2+, OPAQUE memory, multi-frame encode, user plugins\n"\
> +             "and LA_EXT rate control mode in FFmpeg QSV won't be supported." ||
> +            die "ERROR: libvpl >= 2.2 not found"

If you're going to error, then use require_pkg_config().

> +fi
> +
>   if enabled libmfx; then
>      check_cc MFX_CODEC_VP9 "mfxdefs.h mfxstructures.h" "MFX_CODEC_VP9"

Since this is not going to be used with libvpl, you could merge it into 
the libmfx check above.

>   fi
>