Hi Andrew, Here the quick test results. I used 4k sample video on my PC with RX550 and outdated CPU (ten years-old double-core Pentium) The variable CIN_HW_DEV affects only on ability to play videos. My test video with vaapi device plays at full speed with around 50% CPU load. The use of 'none' device results in unplayable video (more like slide show). But in both cases I can successfully encode video with hevc_vaapi and h264_vaapi (profile=main) encoders with about 100% CPU load. The hevc encoder produce smaller file size with a shorter encoding time (that's surprise me). Ten seconds video encodes about 3 minutes (my hardware is really old for 4k:( ) Software encoding lasts forever, so I not tested it. And last test I used ffmpeg from deb-multimedia and created proxy file for my 4k video sample. Hevc_vaapi decode and h264 vaapi encode with vaapi downscale to 640x360 took around 30 seconds for 10 second video!!! If I use cinelerra's to manually create proxy files (not by menu), just add scale_vaapi filter, then I get following results. The hevc and h262 vaapi encoders uses around 1 min 20 sec (hevc) and 1 minute 45 seconds (h262 main). In case of proxy creation with a menu button, rendering estimates around 42 minutes for 30 seconds video. But I not tested it. So my conclusion that vaapi decoding is extremely useful for playing videos and create proxy files in separate script. @GG how can I use custom script for proxy files creation inside Cinelerra? Or use ffmpeg's scale_vaapi filter if vaapi used. $vainfo libva info: VA-API version 0.39.4 libva info: va_getDriverName() returns -1 libva info: User requested driver 'radeonsi' libva info: Trying to open /usr/lib/x86_64-linux-gnu/dri/radeonsi_drv_video.so libva info: Found init function __vaDriverInit_0_39 libva info: va_openDriver() returns 0 vainfo: VA-API version: 0.39 (libva 1.7.3) vainfo: Driver version: Mesa Gallium driver 18.2.8 for Radeon RX 550 Series (POLARIS12, DRM 3.27.0, 4.19.0-0.bpo.4-amd64, LLVM 6.0.0) vainfo: Supported profile and entrypoints VAProfileMPEG2Simple : VAEntrypointVLD VAProfileMPEG2Main : VAEntrypointVLD VAProfileVC1Simple : VAEntrypointVLD VAProfileVC1Main : VAEntrypointVLD VAProfileVC1Advanced : VAEntrypointVLD VAProfileH264ConstrainedBaseline: VAEntrypointVLD VAProfileH264ConstrainedBaseline: VAEntrypointEncSlice VAProfileH264Main : VAEntrypointVLD VAProfileH264Main : VAEntrypointEncSlice VAProfileH264High : VAEntrypointVLD VAProfileH264High : VAEntrypointEncSlice VAProfileHEVCMain : VAEntrypointVLD VAProfileHEVCMain : VAEntrypointEncSlice VAProfileHEVCMain10 : VAEntrypointVLD VAProfileJPEGBaseline : VAEntrypointVLD VAProfileNone : VAEntrypointVideoProc $cat /proc/cpuinfo processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 23 model name : Pentium(R) Dual-Core CPU E5300 @ 2.60GHz stepping : 10 microcode : 0xa0b cpu MHz : 1905.714 cache size : 2048 KB physical id : 0 siblings : 2 core id : 0 cpu cores : 2 apicid : 0 initial apicid : 0 fpu : yes fpu_exception : yes cpuid level : 13 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx lm constant_tsc arch_perfmon pebs bts rep_good nopl cpuid aperfmperf pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm xsave lahf_lm pti tpr_shadow vnmi flexpriority dtherm bugs : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass l1tf bogomips : 5200.12 clflush size : 64 cache_alignment : 64 address sizes : 36 bits physical, 48 bits virtual power management: processor : 1 vendor_id : GenuineIntel cpu family : 6 model : 23 model name : Pentium(R) Dual-Core CPU E5300 @ 2.60GHz stepping : 10 microcode : 0xa0b cpu MHz : 1833.296 cache size : 2048 KB physical id : 0 siblings : 2 core id : 1 cpu cores : 2 apicid : 1 initial apicid : 1 fpu : yes fpu_exception : yes cpuid level : 13 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx lm constant_tsc arch_perfmon pebs bts rep_good nopl cpuid aperfmperf pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm xsave lahf_lm pti tpr_shadow vnmi flexpriority dtherm bugs : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass l1tf bogomips : 5200.12 clflush size : 64 cache_alignment : 64 address sizes : 36 bits physical, 48 bits virtual power management: