About smoothly convert an x264 encoded file to an x265 one.

[aureus]

Hello guys, greatings to you all.

I really have problems on encoding an x264 file to an x265 one. This is a animation video file, and when I watch it, the visual effect is pretty good, it is just a little bigger, so I want to depress it into an x265 one. But here is my problem, no matter what encoding settings I use, the frames of a sample I made of this file would have lost frames, just like frame skipping. Could you help me to figure out what encoding settings should I use in order to 100% make the new file smoothly without any lost frames please?

Really appreciate you guys.

Here are the settings:

General
Unique ID : 181818196067408047654078350392787870080 (0x88C8E92BC425138A8A2AAFD432FA2180)
Complete name : C:\The.Galaxy.Railways.A.Letter.from.the.Abandoned .Planet.2007.1080p.BluRay.x264.mkv
Format : Matroska
Format version : Version 4
File size : 4.73 GiB
Duration : 1 h 30 min
Overall bit rate mode : Variable
Overall bit rate : 7 492 kb/s
Encoded date : 2014-05-31 14:25:19 UTC
Writing application : mkvmerge v6.5.0 ('Isn't she lovely') built on Oct 20 2013 12:50:05
Writing library : libebml v1.3.0 + libmatroska v1.4.1

Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L4.1
Format settings : CABAC / 4 Ref Frames
Format settings, CABAC : Yes
Format settings, Reference fra : 4 frames
Codec ID : V_MPEG4/ISO/AVC
Nominal bit rate : 6 800 kb/s
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate mode : Variable
Original frame rate : 29.970 FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.109
Writing library : x264 core 125 r2200 999b753
Encoding settings : cabac=1 / ref=4 / deblock=1:-1:-1 / analyse=0x3:0x113 / me=umh / subme=9 / psy=1 / psy_rd=1.00:0.00 / mixed_ref=1 / me_range=24 / chroma_me=1 / trellis=2 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=-2 / threads=18 / lookahead_threads=3 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / bluray_compat=0 / constrained_intra=0 / bframes=3 / b_pyramid=0 / b_adapt=2 / b_bias=0 / direct=3 / weightb=1 / open_gop=0 / weightp=2 / keyint=300 / keyint_min=29 / scenecut=40 / intra_refresh=0 / rc_lookahead=50 / rc=2pass / mbtree=1 / bitrate=6800 / ratetol=1.0 / qcomp=0.60 / qpmin=10 / qpmax=51 / qpstep=4 / cplxblur=20.0 / qblur=0.5 / vbv_maxrate=50000 / vbv_bufsize=50000 / nal_hrd=none / ip_ratio=1.40 / aq=1:1.00
Default : Yes
Forced : No

Audio
ID : 2
Format : FLAC
Format/Info : Free Lossless Audio Codec
Codec ID : A_FLAC
Duration : 1 h 30 min
Bit rate mode : Variable
Channel(s) : 2 channels
Channel layout : L R
Sampling rate : 48.0 kHz
Bit depth : 16 bits
Compression mode : Lossless
Title : FLAC 2.0
Writing library : libFLAC 1.2.1 (2007-09-17)
Language : Japanese
Default : Yes
Forced : No
MD5 of the unencoded content : 071239EF8349A3BD239AB5B7E4BF7B3B

Menu
00:00:00.000 : en:Logo
00:00:22.356 : en:Chapter 01
00:06:30.991 : en:Chapter 02
00:15:03.336 : en:Chapter 03
00:22:27.246 : en:Chapter 04
00:29:05.077 : en:Chapter 05
00:36:36.694 : en:Chapter 06
00:46:00.758 : en:Chapter 07
00:56:31.388 : en:Chapter 08
01:07:34.617 : en:Chapter 09
01:17:58.841 : en:Chapter 10
01:23:53.996 : en:Chapter 11
01:27:42.357 : en:Chapter 12(Ending)

[Selur]

Frame rate mode : Variable
Original frame rate : 29.970 FPS

You need to make sure to either decode to cfr or copy the time codes from the source video.
If you don't know how to do that, you might want to read up on it.

Cu Selur

[ProWo]

... it is just a little bigger, so I want to depress it into an x265 one.

Instead of re-encoding the video stream, you could also reduce the size of the audio stream by compressing it to ac3 265 kb/s cbr, for example. Flac takes up a lot of space.

[hello_hello]

Uploading a small sample of the video might help.

[aureus]

Uploading a small sample of the video might help.

https://forum.videohelp.com/attachment.php?attachmentid=90304&stc=1&d=1766073272
Hi, thanks man. This is the sample I tried, and it is also that very sample which I can't make it right.

[hello_hello]

That sample had a 1876 ms video delay when I remuxed it as an MKV, so I remuxed it again while removing the delay so it wouldn't confuse things.

Frame rate mode : Variable
Frame rate : 23.853 FPS
Original frame rate : 29.970 (30000/1001) FPS

Original frame rate is the frame rate written to the video stream. It can be different to the container frame rate if the video has been remuxed while changing the frame rate, but in a perfect world a decoder would use the container frame rate.

It appears to be variable, but every source filter I tried to open it in Avisynth decoded it at exactly 23.976 fps. I suspect that's the correct frame rate as if it's variable the source filters decode at the average frame rate. It still could be variable, but it seems unlikely that 23.976 fps just happens to be the average frame rate of a variable source. Anything's possible though....

How does this seem? Playback often begins a little jittery on my PC before it settles down so it's hard for me to tell with a short sample. I think it's okay though as it doesn't seem any more jittery than the original sample. I re-encoded it with both x264 and x265.

PS. I forgot to ask... what program are using using to re-encode it?

[aureus]

Thanks man, I spent hours on trying to make it right, but failed. It seems you only spent minutes, it is just like Professionals do professional stuffs. Answer your question, I used ffmpeg v8.0 on Win10, could you send me the comands you used so I can test on the whole video to make a sample please?

[hello_hello]

I literally only opened it in Avisynth+ and re-encoded it (after remuxing it as an mkv). It just happened to be decoded correctly (I assume) by the FFMS2 source filter.

I'd suggest trying this. Open the MP4 with MKVToolNixGUI, and under the "Timestamps and default duration" section, specify 24000/1001p as the frame rate for the video stream. The default MKVToolNixGUI layout looks different to this, and it's the Linux version, but the screenshot below should help you find the right spot.
Once that's done, save it as an MKV, which should have a constant frame rate. Open it in a player and navigate around a bit to make sure the audio is always in sync. If it's not, the original MP4 is probably variable frame rate and an ffmpeg expert might have to help you with it as I'm not one. If the audio is in sync, try re-encoding the MKV with ffmpeg to see how it goes.


[Attachment 90318 - Click to enlarge]

PS. Here's your sample, remuxed as an MKV with the video delay removed. MediaInfo still shows it as variable frame rate, but it's the sample I re-encoded.

[jagabo]

The ffmpeg command line can be as simple as:

ffmpeg -i input.mp4 -c:v libx265 -c:a copy output.mp4

[Henryk69]

I have two identical videos, one that plays faster at 25 fps and the other that plays slower at 23.975812 fps. How can I make both videos play at the same speed?

[ProWo]

I have two identical videos, one that plays faster at 25 fps and the other that plays slower at 23.975812 fps. How can I make both videos play at the same speed?

If the videocodec is avc (h264) or hevc (h265) you can use clever FFmpeg-GUI.
There is a feature to convert the framerate lossless without reencoding.
(Lossless changes, change framerate)
Only the videostream is changed; audio and subtitles must be adapted separately.

[videoAI]

@aureus

Sample 银河铁道物语-被时间遗忘的.mp4

What media info (from mpc-be) sees at video stream:
---
Frame rate mode : Variable
Frame rate : 23.976 (23976/1000) FPS
Minimum frame rate : 23.810 FPS
Maximum frame rate : 24.390 FPS
Original frame rate : 29.970 (30000/1001) FPS

what ffprobe sees:
---
r_frame_rate: 24000/1001 = 23.976
avg_frame_rate: 197000/8217 = 23.974

Metadata Editor view (uses ffprobe):


[Attachment 90391 - Click to enlarge]

MediaInfo typically displays frame rate information in several ways:
- Original frame rate: The exact frame rate of the source video
- Encoded frame rate: The frame rate used during video encoding
- Displayed frame rate: The frame rate used when playing the video

The original frame rate is the native or source frame rate of a video file.
Importance of Original Frame Rate:
- Helps understand the source video's native recording conditions
- Indicates the video's original capture characteristics
- Useful for video conversion and editing

Common Frame Rates:
| Frame Rate | Typical Use |
|-----------|-------------|
| 23.976 fps | Film/cinema standard |
| 24 fps | Cinema standard |
| 25 fps | PAL video standard |
| 29.97 fps | NTSC video standard |
| 30 fps | Modern digital video |
| 50 fps | High-frame-rate video |
| 60 fps | High-motion video games, sports |

[Henryk69]

Thank you : ProWo , videoAI for the quick reply

[Henryk69]

these are two videos with different fps

[Henryk69]

now I will change fps 25 to 23

[Henryk69]

I used the clever FFmpeg GUI and compressed from 25 fps to 23.976. After compressing and changing the fps to 23.976 from 25 fps, it's almost perfect, but after a while, there's a slight 2-second delay compared to the original with 23.975812 fps.

[Henryk69]

I'd like to point out that these two files have different lengths. times
1.1.36.01
2.1.36.02

Maybe this is the reason for the missing second, preventing it from lagging. I even tried changing the audio stream from 48,000 to 44,100 in the Clever FFmpeg GUI, but there's still a 1-second delay.