View Full Version : HDR to SDR StaxRip Problem
jay123210599
9th January 2026, 17:55
I am having this problem in StaxRip: https://github.com/staxrip/staxrip/issues/1891
One guy said: "Dolby Vision requires YCbCr 4:2:0 color space. Just make sure you convert the video (back) to YUV420 before you send it to x265." But how do I convert the video (back) before I send it?
Z2697
9th January 2026, 20:04
why you trying use dovi if convert to sdr
but yeah the upscaled chroma is not good anyway
GeoffreyA
9th January 2026, 21:02
Is there an option in StaxRip for output pixel format?
As an alternative, you can try in FFmpeg:
ffmpeg -init_hw_device vulkan -i SOURCE.mkv -map 0:v:0 -map_metadata -1
-vf libplacebo=w=-1:h=1080:upscaler=spline36:downscaler=spline36:colorspace=bt709:color_trc=bt709:color_primaries=bt709:range=limited:format=yuv420p10le,sidedata=delete
-c:v libx265 -preset slow -crf 18 -x265-params level-idc=41:no-sao=1:deblock=-1,-1:aq-mode=1 OUT.mp4
The x265 parameters should be tuned further but that is beyond the scope of this thread.
manolito
10th January 2026, 17:12
Hi jay123210599,
could you upload a short cutout of your source clip, and also your desired target format and frame size? My conversion options are limited to DGHDRtoSDR for Avisynth+ (using old StaxRip 32bit version), and to zimg based scripts for FFmpeg.
Cheers
manolito
Columbo
10th January 2026, 17:40
@jay
DGHDRtoSDR() can output 4:2:0 with fulldepth=false (default). Note it runs on Avisynth+ or Vapoursynth. It's intended for an nVidia graphics card. However, you can run it in software mode with impl="sw", but it's rather slow. Other filters like libplacebo would be faster. That should be enough to get you going using a manual approach with avisynth+/vapoursynth/x265. I cannot help with staxrip, due to my ignorance of it, and not anything against staxrip, which is a fine application.
Like Z2697 said, what are you talking about if you are going to SDR?
jay123210599
11th January 2026, 02:20
why you trying use dovi if convert to sdr
but yeah the upscaled chroma is not good anyway
Dolby Vision was the HDR format for my video.
Z2697
11th January 2026, 05:23
Yeah. Was. W-A-S !
Columbo
11th January 2026, 09:33
Great answer Z man. I fear the OP may still not get the point, however.
jay123210599
11th January 2026, 13:59
Great answer Z man. I fear the OP may still not get the point, however.
Here's my point: How do I convert my video (back) to YUV420 before I send it to x265?
microchip8
11th January 2026, 14:22
Here's my point: How do I convert my video (back) to YUV420 before I send it to x265?
Look in StaxRip for pixel format.
For ffmpeg, see example above by GeoffreyA (the format= filter)
What did you not understand?
GeoffreyA
11th January 2026, 14:41
Post a screenshot of the dialogue boxes. I am guessing that near to where you selected Placebo, the output pixel format will be. Perhaps it's set to YUV444. Then, set DV to None.
jay123210599
11th January 2026, 16:02
@microchip8 @GeoffreyA
Here's my dialogue boxes: https://imgbox.com/BL44UHX3 https://imgbox.com/qdtQrWUZ
microchip8
11th January 2026, 16:41
Your input is already YUV420! There is no conversion needed.
jay123210599
11th January 2026, 17:46
All right, but now I have this error.
vpy [INFO]: using external VapourSynth library from: "C:\Users\Jalen\Documents\StaxRip\Apps\FrameServer\VapourSynth\VSScript.dll"
vpy [INFO]: VapourSynth Core R73
Allocation of size 252K failed: VK_ERROR_OUT_OF_DEVICE_MEMORY!
Memory heaps supported by device:
0: flags 0x1 size 23G
1: flags 0x0 size 15G
2: flags 0x1 size 214M
Memory pool 0:
Compatible types: 0x3
Optimal flags: 0x1
Slab 0: 8 x 15M: 24M used 47M res 63M alloc from heap 0, efficiency 50.98% [../subprojects/libplacebo/src/utils/upload.c:239]
Pool summary: 24M used 47M res 63M alloc, efficiency 50.98%, utilization 75.00%
Memory pool 1:
Compatible types: 0xffffffff
Optimal flags: 0x3
Buffer flags: 0x3
Slab 0: 8 x 15M: 22M used 45M res 60M alloc from heap 0, efficiency 50.00% [../subprojects/libplacebo/src/gpu/utils.c:576]
Pool summary: 22M used 45M res 60M alloc, efficiency 50.00%, utilization 75.00%
Memory pool 2:
Compatible types: 0xffffffff
Required flags: 0x1
Optimal flags: 0x2
Buffer flags: 0xc3
Pool summary: 0 used 0 res 0 alloc, efficiency 100.00%, utilization 100.00%
Memory summary: 47M used 93M res 124M alloc, efficiency 50.50%, utilization 75.00%, max page: 1520M
Backtrace:
#0 0x7ff81c4769ed in pl_vulkan_release_ex+0x748d (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x869ed) (0x240ac69ed)
#1 0x7ff81c478042 in pl_vulkan_release_ex+0x8ae2 (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x88042) (0x240ac8042)
#2 0x7ff81c46ac82 in pl_vulkan_sem_create+0x1082 (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x7ac82) (0x240abac82)
#3 0x7ff81c452f01 in pl_buf_create+0x211 (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x62f01) (0x240aa2f01)
#4 0x7ff81c459618 in pl_timer_query+0x44f8 (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x69618) (0x240aa9618)
#5 0x7ff81c454ab0 in pl_pass_run+0x420 (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x64ab0) (0x240aa4ab0)
#6 0x7ff81c43dfcc in pl_find_error_diffusion_kernel+0x54c (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x4dfcc) (0x240a8dfcc)
#7 0x7ff81c4416a7 in pl_dispatch_finish+0x747 (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x516a7) (0x240a916a7)
#8 0x7ff81c3fe222 in VapourSynthPluginInit2+0xcb92 (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0xe222) (0x240a4e222)
#9 0x7ff81c3ffea2 in VapourSynthPluginInit2+0xe812 (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0xfea2) (0x240a4fea2)
#10 0x7ff81c40a7a1 in pl_render_image+0xc1 (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x1a7a1) (0x240a5a7a1)
#11 0x7ff81c3f2937 in VapourSynthPluginInit2+0x12a7 (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x2937) (0x240a42937)
#12 0x7ff81c3f2c8f in VapourSynthPluginInit2+0x15ff (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x2c8f) (0x240a42c8f)
#13 0x7ff81c3f3980 in VapourSynthPluginInit2+0x22f0 (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x3980) (0x240a43980)
#14 0x7ff8743c796c in getVapourSynthAPI+0xdf0c (C:\Users\Jalen\Documents\StaxRip\Apps\FrameServer\VapourSynth\Lib\site-packages\VapourSynth.dll+0x10796c) (0x18010796c)
#15 0x7ff8743daa22 in getVapourSynthAPI+0x20fc2 (C:\Users\Jalen\Documents\StaxRip\Apps\FrameServer\VapourSynth\Lib\site-packages\VapourSynth.dll+0x11aa22) (0x18011aa22)
#16 0x7ff8743dc2d5 in getVapourSynthAPI+0x22875 (C:\Users\Jalen\Documents\StaxRip\Apps\FrameServer\VapourSynth\Lib\site-packages\VapourSynth.dll+0x11c2d5) (0x18011c2d5)
#17 0x7ff91dd537af in wcsrchr+0x14f (C:\WINDOWS\System32\ucrtbase.dll+0x37af) (0x1800037af)
#18 0x7ff92051e8d6 in BaseThreadInitThunk+0x16 (C:\WINDOWS\System32\KERNEL32.DLL+0x2e8d6) (0x18002e8d6)
#19 0x7ff920c8c53b in RtlUserThreadStart+0x2b (C:\WINDOWS\SYSTEM32\ntdll.dll+0x8c53b) (0x18008c53b)
for malloc: ../subprojects/libplacebo/src/gpu/utils.c:1175
No slab to serve request for 96 bytes (with alignment 0xc00) in pool 2!
Failed allocating vertex buffer!
Allocation of size 252K failed: VK_ERROR_OUT_OF_DEVICE_MEMORY!
Memory heaps supported by device:
0: flags 0x1 size 23G
1: flags 0x0 size 15G
2: flags 0x1 size 214M
Memory pool 0:
Compatible types: 0x3
Optimal flags: 0x1
Slab 0: 8 x 15M: 24M used 47M res 63M alloc from heap 0, efficiency 50.98% [../subprojects/libplacebo/src/utils/upload.c:239]
Slab 1: fffe x 16K: 16K used 16K res 256K alloc from heap 0, efficiency 100.00% [subprojects/libplacebo/src/shaders/sampling.c:1032]
Pool summary: 24M used 47M res 64M alloc, efficiency 51.00%, utilization 74.73%
Memory pool 1:
Compatible types: 0xffffffff
Optimal flags: 0x3
Buffer flags: 0x3
Slab 0: 8 x 15M: 22M used 45M res 60M alloc from heap 0, efficiency 50.00% [../subprojects/libplacebo/src/gpu/utils.c:576]
Pool summary: 22M used 45M res 60M alloc, efficiency 50.00%, utilization 75.00%
Memory pool 2:
Compatible types: 0xffffffff
Required flags: 0x1
Optimal flags: 0x2
Buffer flags: 0xc3
Pool summary: 0 used 0 res 0 alloc, efficiency 100.00%, utilization 100.00%
Memory summary: 47M used 93M res 124M alloc, efficiency 50.51%, utilization 74.86%, max page: 1520M
Backtrace:
#0 0x7ff81c4769ed in pl_vulkan_release_ex+0x748d (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x869ed) (0x240ac69ed)
#1 0x7ff81c478042 in pl_vulkan_release_ex+0x8ae2 (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x88042) (0x240ac8042)
#2 0x7ff81c46ac82 in pl_vulkan_sem_create+0x1082 (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x7ac82) (0x240abac82)
#3 0x7ff81c452f01 in pl_buf_create+0x211 (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x62f01) (0x240aa2f01)
#4 0x7ff81c457588 in pl_timer_query+0x2468 (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x67588) (0x240aa7588)
#5 0x7ff81c46d8ea in pl_vulkan_sem_create+0x3cea (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x7d8ea) (0x240abd8ea)
#6 0x7ff81c452b4c in pl_tex_upload+0x7c (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x62b4c) (0x240aa2b4c)
#7 0x7ff81c46ee30 in pl_vulkan_wrap+0x1350 (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x7ee30) (0x240abee30)
#8 0x7ff81c42a6eb in pl_lut_parse_cube+0x247b (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x3a6eb) (0x240a7a6eb)
#9 0x7ff81c42f87d in pl_shader_sample_ortho2+0x32d (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x3f87d) (0x240a7f87d)
#10 0x7ff81c3ff3b1 in VapourSynthPluginInit2+0xdd21 (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0xf3b1) (0x240a4f3b1)
#11 0x7ff81c400adb in VapourSynthPluginInit2+0xf44b (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x10adb) (0x240a50adb)
#12 0x7ff81c40a7a1 in pl_render_image+0xc1 (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x1a7a1) (0x240a5a7a1)
#13 0x7ff81c3f2937 in VapourSynthPluginInit2+0x12a7 (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x2937) (0x240a42937)
#14 0x7ff81c3f2c8f in VapourSynthPluginInit2+0x15ff (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x2c8f) (0x240a42c8f)
#15 0x7ff81c3f3980 in VapourSynthPluginInit2+0x22f0 (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x3980) (0x240a43980)
#16 0x7ff8743c796c in getVapourSynthAPI+0xdf0c (C:\Users\Jalen\Documents\StaxRip\Apps\FrameServer\VapourSynth\Lib\site-packages\VapourSynth.dll+0x10796c) (0x18010796c)
#17 0x7ff8743daa22 in getVapourSynthAPI+0x20fc2 (C:\Users\Jalen\Documents\StaxRip\Apps\FrameServer\VapourSynth\Lib\site-packages\VapourSynth.dll+0x11aa22) (0x18011aa22)
#18 0x7ff8743dc2d5 in getVapourSynthAPI+0x22875 (C:\Users\Jalen\Documents\StaxRip\Apps\FrameServer\VapourSynth\Lib\site-packages\VapourSynth.dll+0x11c2d5) (0x18011c2d5)
#19 0x7ff91dd537af in wcsrchr+0x14f (C:\WINDOWS\System32\ucrtbase.dll+0x37af) (0x1800037af)
#20 0x7ff92051e8d6 in BaseThreadInitThunk+0x16 (C:\WINDOWS\System32\KERNEL32.DLL+0x2e8d6) (0x18002e8d6)
#21 0x7ff920c8c53b in RtlUserThreadStart+0x2b (C:\WINDOWS\SYSTEM32\ntdll.dll+0x8c53b) (0x18008c53b)
for malloc: ../subprojects/libplacebo/src/gpu/utils.c:576
No slab to serve request for 8192 bytes (with alignment 0xc00) in pool 1!
Failed creating LUT texture!
Failed initializing separated LUT!
Failed dispatching scaler.. disabling
Allocation of size 252K failed: VK_ERROR_OUT_OF_DEVICE_MEMORY!
Memory heaps supported by device:
0: flags 0x1 size 23G
1: flags 0x0 size 15G
2: flags 0x1 size 214M
Memory pool 0:
Compatible types: 0x3
Optimal flags: 0x1
Slab 0: 8 x 15M: 24M used 47M res 63M alloc from heap 0, efficiency 50.98% [../subprojects/libplacebo/src/utils/upload.c:239]
Slab 1: fffe x 16K: 8192 used 16K res 256K alloc from heap 0, efficiency 50.00% [subprojects/libplacebo/src/shaders/colorspace.c:1857]
Pool summary: 24M used 47M res 64M alloc, efficiency 50.98%, utilization 74.73%
Memory pool 1:
Compatible types: 0xffffffff
Optimal flags: 0x3
Buffer flags: 0x3
Slab 0: 8 x 15M: 22M used 45M res 60M alloc from heap 0, efficiency 50.00% [../subprojects/libplacebo/src/gpu/utils.c:576]
Pool summary: 22M used 45M res 60M alloc, efficiency 50.00%, utilization 75.00%
Memory pool 2:
Compatible types: 0xffffffff
Required flags: 0x1
Optimal flags: 0x2
Buffer flags: 0xc3
Pool summary: 0 used 0 res 0 alloc, efficiency 100.00%, utilization 100.00%
Memory summary: 47M used 93M res 124M alloc, efficiency 50.50%, utilization 74.86%, max page: 1520M
Backtrace:
#0 0x7ff81c4769ed in pl_vulkan_release_ex+0x748d (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x869ed) (0x240ac69ed)
#1 0x7ff81c478042 in pl_vulkan_release_ex+0x8ae2 (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x88042) (0x240ac8042)
#2 0x7ff81c46ac82 in pl_vulkan_sem_create+0x1082 (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x7ac82) (0x240abac82)
#3 0x7ff81c452f01 in pl_buf_create+0x211 (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x62f01) (0x240aa2f01)
#4 0x7ff81c457588 in pl_timer_query+0x2468 (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x67588) (0x240aa7588)
#5 0x7ff81c46d8ea in pl_vulkan_sem_create+0x3cea (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x7d8ea) (0x240abd8ea)
#6 0x7ff81c452b4c in pl_tex_upload+0x7c (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x62b4c) (0x240aa2b4c)
#7 0x7ff81c429817 in pl_lut_parse_cube+0x15a7 (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x39817) (0x240a79817)
#8 0x7ff81c4169e3 in pl_shader_color_map_ex+0x2013 (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x269e3) (0x240a669e3)
#9 0x7ff81c4033b0 in VapourSynthPluginInit2+0x11d20 (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x133b0) (0x240a533b0)
#10 0x7ff81c40a813 in pl_render_image+0x133 (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x1a813) (0x240a5a813)
#11 0x7ff81c3f2937 in VapourSynthPluginInit2+0x12a7 (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x2937) (0x240a42937)
#12 0x7ff81c3f2c8f in VapourSynthPluginInit2+0x15ff (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x2c8f) (0x240a42c8f)
#13 0x7ff81c3f3980 in VapourSynthPluginInit2+0x22f0 (C:\Users\Jalen\Documents\StaxRip\Apps\Plugins\VS\libvs_placebo\libvs_placebo.dll+0x3980) (0x240a43980)
#14 0x7ff8743c796c in getVapourSynthAPI+0xdf0c (C:\Users\Jalen\Documents\StaxRip\Apps\FrameServer\VapourSynth\Lib\site-packages\VapourSynth.dll+0x10796c) (0x18010796c)
#15 0x7ff8743daa22 in getVapourSynthAPI+0x20fc2 (C:\Users\Jalen\Documents\StaxRip\Apps\FrameServer\VapourSynth\Lib\site-packages\VapourSynth.dll+0x11aa22) (0x18011aa22)
#16 0x7ff8743dc2d5 in getVapourSynthAPI+0x22875 (C:\Users\Jalen\Documents\StaxRip\Apps\FrameServer\VapourSynth\Lib\site-packages\VapourSynth.dll+0x11c2d5) (0x18011c2d5)
#17 0x7ff91dd537af in wcsrchr+0x14f (C:\WINDOWS\System32\ucrtbase.dll+0x37af) (0x1800037af)
#18 0x7ff92051e8d6 in BaseThreadInitThunk+0x16 (C:\WINDOWS\System32\KERNEL32.DLL+0x2e8d6) (0x18002e8d6)
#19 0x7ff920c8c53b in RtlUserThreadStart+0x2b (C:\WINDOWS\SYSTEM32\ntdll.dll+0x8c53b) (0x18008c53b)
for malloc: ../subprojects/libplacebo/src/gpu/utils.c:576
No slab to serve request for 1024 bytes (with alignment 0xc00) in pool 1!
Failed creating LUT texture!
Failed generating tone-mapping LUT!
Attempting to modify a failed shader!
Trying to dispatch a failed shader.
Failed rendering image!
vpy [WARN]: Failed processing planes!
vpy [INFO]: 3840x2076 fps 24000/1001 i444p16 frames 0 - 76 of 77
vpy [INFO]: using 12 parallel requests
raw [INFO]: output file: C:\Users\Jalen\Desktop\New folder (2)\The SpongeBob SquarePants Movie (2004) (2160p BluRay x265 HEVC 10bit HDR DV EAC3 5.1 KLRK)-00.31.57.19-00.32.01.16.mkv_temp\The SpongeBob SquarePants Movie (2004) (2160p BluRay x265 HEVC 10bit HDR DV EAC3 5.1 KLRK)-00.31.57.19-00.32.01.16_new_out.hevc
x265 [INFO]: HEVC encoder version 4.1+212+35-87f5a69a8 [Mod by Patman]
x265 [INFO]: build info [Windows][Clang 21.1.7][64 bit] 10bit
x265 [INFO]: using cpu capabilities: MMX2 SSE2Fast LZCNT SSSE3 SSE4.2 AVX FMA3 BMI2 AVX2
x265 [FLAW]: Dolby Vision profile - 5, profile - 8.1, profile - 8.2 and profile - 8.4 requires YCbCr 4:2:0 color space
x265 [FLAW]: x265_encoder_open() failed for Enc,
Allocation of size 252K failed: VK_ERROR_OUT_OF_DEVICE_MEMORY!
GeoffreyA
12th January 2026, 19:36
Could be a driver issue. On my Arc B580, libplacebo does not work through VapourSynth. If I remember correctly, you've got an Nvidia card. I would consider using FFmpeg, which is simpler.
Z2697
13th January 2026, 05:47
On the 444 regard, vsplacebo tonemap ONLY outputs RGB48 or YUV444P16, depending on input color family.
(The reason I said "upscaled chroma")
Pixel format conversion is covered by core.resize
plug it in after vsplacebo
jay123210599
13th January 2026, 17:23
@GeoffreyA @Z2697
I switched over to AviSynth and that solved the error, but now it's saying "Dolby Vision requires YCbCr 4:2:0 color space", even though my input video is already YUV420. How do I fix that?
GeoffreyA
13th January 2026, 18:13
Jay, as Z2967 noted, convert it using a resize filter after the tone mapping. Seemingly, placebo is outputting YUV444.
microchip8
13th January 2026, 19:29
@GeoffreyA @Z2697
I switched over to AviSynth and that solved the error, but now it's saying "Dolby Vision requires YCbCr 4:2:0 color space", even though my input video is already YUV420. How do I fix that?
YCbCr420 and YUV420 are virtually the same. The former is a "digital" format, the latter comes from the analog era. Something is outputting a different format in your chain. As others noted, add a converting filter at the end of the filter chain.
jay123210599
13th January 2026, 21:58
Where in any of these codes are outputting YUV444?
ConvertBits(16)
libplacebo_Tonemap(src_csp=3, dst_csp=0, dynamic_peak_detection=True, tone_mapping_function="bt2390", contrast_recovery=0.3, contrast_smoothness=3.5)
# ConvertBits(10)
# ConvertToYUV420()
--crf 10 --dolby-vision-profile 8.1 --dolby-vision-rpu "C:\Users\User\Desktop\New folder (2)\4K HDR.mkv_temp\HDRDVmetadata.rpu" --output-depth 10 --vbv-bufsize 160000 --vbv-maxrate 160000 --range limited --colorprim bt2020 --transfer smpte2084 --colormatrix bt2020nc --chromaloc 2 --master-display "G(13250,34500)B(7500,3000)R(34000,16000)WP(15635,16450)L(10000000,1)" --max-cll "1000,257" --hdr10 --repeat-headers --hrd --aud
Z2697
14th January 2026, 02:59
Reading is a hard to learn skill it seems.
jay123210599
16th January 2026, 03:17
@Z2697 @GeoffreyA
All right, I'm sending you my HDR video. Use Placebo on StaxRip and see if you could fix the error.
https://www.mediafire.com/file/fn71jqfl3odrsr2/HDR.mkv/file
GeoffreyA
16th January 2026, 12:42
I tried it and this is what I found. You've got to double-click on Placebo in the filter list on the left, then uncomment the following lines:
ConvertToYUV420()
ConvertBits(10)
However, x265 still fails because it thinks it is receiving HDR input. So, open x265 options. Under "Input," remove all Dolby Vision settings, such as the profile and RPU. Then, under "VUI," set Colorprim, Transfer, and Colormatrix to BT.709. Lastly, under "VUI 2," remove all HDR light settings, setting CLL and FALL to 0, deselecting "Emit content light," and removing Master Display information. If you know the correct x265 profile, level, and tier, set it under "Basic." 10-bit 1080p SDR content should be Main10, Level 4.1, High Tier.
All in all, it should work, but I think it's simpler to use FFmpeg directly. Generally, changes one makes are sent downstream to the rest of the pipeline, making it automatic.
jay123210599
16th January 2026, 13:49
I tried it and this is what I found. You've got to double-click on Placebo in the filter list on the left, then uncomment the following lines:
ConvertToYUV420()
ConvertBits(10)
However, x265 still fails because it thinks it is receiving HDR input. So, open x265 options. Under "Input," remove all Dolby Vision settings, such as the profile and RPU. Then, under "VUI," set Colorprim, Transfer, and Colormatrix to BT.709. Lastly, under "VUI 2," remove all HDR light settings, setting CLL and FALL to 0, deselecting "Emit content light," and removing Master Display information. If you know the correct x265 profile, level, and tier, set it under "Basic." 10-bit 1080p SDR content should be Main10, Level 4.1, High Tier.
All in all, it should work, but I think it's simpler to use FFmpeg directly. Generally, changes one makes are sent downstream to the rest of the pipeline, making it automatic.
I just uncommented those lines and that worked, but I have one more problem. When playing the outputted video in PotPlayer, the video still had the HDR tag even though it has been converted to SDR. How do I change that?
https://imgbox.com/qqC31GFI
GeoffreyA
16th January 2026, 13:54
As above, go into x265 options, removing everything related to Dolby Vision and HDR, and importantly, setting the colour matrix, transfer, and primaries to BT.709. That should do it. In MediaInfo, there should be no sign of BT.2020, DV, or anything of that sort. If the problem persists, post the MediaInfo properties of the encoded file.
manolito
16th January 2026, 15:14
Hi,
here is my simple version which does not use LibPlacebo (my old Thinkpad does not support it). In my upload there are 3 different versions using DGHDRtoSDR, plus 2 zimg based versions. My target format is X264, because it is easier to use and in my view it offers better quality.
Here is the link: (only valid for 3 days)
https://we.tl/t-j17Hrq58fP
Cheers
manolito
EDIT:
Sorry for the typo in the readme. In the second line of cource I mean "Video" and not "Audio"
jay123210599
16th January 2026, 17:01
Can SDR videos have color primaries and matrix coefficients of BT.2020?
GeoffreyA
16th January 2026, 18:18
Can SDR videos have color primaries and matrix coefficients of BT.2020?
I don't think the matrix and primaries can be, but perhaps the BT.2020 transfer function. At any rate, it's advisable to stick with 709 for all three.
FranceBB
17th January 2026, 22:05
Also, given that it's not guaranteed that libplacebo has updated the frame properties, make sure they're all set to BT709 now in Avisynth so that anything downstream will know.
Put those at the end of the script:
#Remove bad frame properties
propclearall()
#Populate frame properties correctly
propSet("_ColorRange", 1) #Limited TV Range
propSet("_Matrix", 1) #BT709
propSet("_Transfer", 1) #BT709
propSet("_Primaries", 1) #BT709
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