For me worked just with
# yum install ffmpeg-2.6.4-1.fc22.x86_64.rpm
And automatically asked authorization to dowload the depedencies. Below the example, i am using fedora 22
[root@localhost lukas]# yum install ffmpeg-2.6.4-1.fc22.x86_64.rpm
Yum command has been deprecated, redirecting to '/usr/bin/dnf install ffmpeg-2.6.4-1.fc22.x86_64.rpm'.
See 'man dnf' and 'man yum2dnf' for more information.
To transfer transaction metadata from yum to DNF, run:
'dnf install python-dnf-plugins-extras-migrate && dnf-2 migrate'
Last metadata expiration check performed 0:28:24 ago on Fri Sep 25 12:43:44 2015.
Dependencies resolved.
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Package Arch Version Repository Size
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Installing:
SDL x86_64 1.2.15-17.fc22 fedora 214 k
ffmpeg x86_64 2.6.4-1.fc22 @commandline 1.5 M
ffmpeg-libs x86_64 2.6.4-1.fc22 rpmfusion-free-updates 5.0 M
fribidi x86_64 0.19.6-3.fc22 fedora 69 k
lame-libs x86_64 3.99.5-5.fc22 rpmfusion-free 345 k
libass x86_64 0.12.1-1.fc22 updates 85 k
libavdevice x86_64 2.6.4-1.fc22 rpmfusion-free-updates 75 k
libdc1394 x86_64 2.2.2-3.fc22 fedora 124 k
libva x86_64 1.5.1-1.fc22 fedora 79 k
openal-soft x86_64 1.16.0-5.fc22 fedora 292 k
opencv-core x86_64 2.4.11-5.fc22 updates 1.9 M
openjpeg-libs x86_64 1.5.1-14.fc22 fedora 89 k
schroedinger x86_64 1.0.11-7.fc22 fedora 315 k
soxr x86_64 0.1.2-1.fc22 updates 83 k
x264-libs x86_64 0.142-12.20141221git6a301b6.fc22 rpmfusion-free 587 k
x265-libs x86_64 1.6-1.fc22 rpmfusion-free 486 k
xvidcore x86_64 1.3.2-6.fc22 rpmfusion-free 264 k
Transaction Summary
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Install 17 Packages
Total size: 11 M
Total download size: 9.9 M
Installed size: 35 M
Is this ok [y/N]: y