Answers.Body: <p>Input and output video formats are from the same generation (similar quality for similar bitrate). Handbrake default settings are prioritizing smaller size over better quality. Video bitrate is divided by 10, which is seriously impacting quality. Not so much because input is strongly standardized (Blu-ray) and Blu-ray tools are not optimized, but 2.5 Mbps is still low for HD, recommended bitrate for HD compressed in AVC are more around 5-10 Mbps.</p>
  <p>Input and output audio formats are very different, input is lossless and output is lossy compressed, not speaking about the channel count (from 5.1 to stereo). This is a serious loss, and not speaking about the trashed French track...</p>
  <p>Input subtitles tracks are not big, but trashed.</p>
  <p>You say &quot;with same quality&quot;, which is totally wrong (for both video and 1st audio), and some data is completely lost (2nd audio track + all subtitle tracks). The right sentence is &quot;with a quality I accept for personal reasons&quot;. If all the quality and data loss is acceptable for you (for example you plan to only watch this film on your laptop during a noisy travel, and never on a big TV with a 5.1 soundbar in a quite room), go for it, else tweak Handbrake e.g. at the minimum for a not too bad experience on TV+soundbar 5 Mbps video + 5.1 512 kbps AAC for both audio tracks + copy of subtitle tracks (for 2nd audio and all subtitles: if you don't want to trash them, else it is fine to trash them). This would lead to a 6 GB file in your case.</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-06-26T11:57:59.630Z
Answers.Text: Thank you very much for this very qualitative response! I will follow your advice.
Answers.UserDisplayName: geo667
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-06-30T18:41:19.727Z
Answers.Text: Sorry, I have another question : what mean cursor named "Constant Quality" in Handbrake (Video tab) : when I use your recommended configuration and a value of 23 for it, I have only a 2,5GB video. 23 is the recommended value for hight definition source say the documentation. I don't understand how to use this parameter.
Answers.UserDisplayName: geo667
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-07-01T06:01:15.460Z
Answers.Text: You can have a global overview of of this settings on e.g. https://slhck.info/video/2017/02/24/crf-guide.html , and 23 is usually OK, here if you have such small file with this setting it may just need that your video content is easy to compress, it may do a bigger file with another content (the quality is constant, not the file size). You may try a lower value for better quality, e.g. 20. Handbrake recommends 20-24 for HD https://handbrake.fr/docs/en/latest/workflow/adjust-quality.html.
Answers.UserDisplayName: Jérôme Martinez
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-07-01T19:44:59.037Z
Answers.Text: Thanks Jérôme !
Answers.UserDisplayName: geo667
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-06-26T06:25:58.850Z
Answers.LastActivityDate: 2020-06-26T06:25:58.850Z
Answers.UserDisplayName: Jérôme Martinez
Body: <p>I have used handbrake on a 40GB video.
  I only have choosed mp4 format and launched the work.
  After few hours of work, I obtain a 2GB video, with same quality...</p>
  <p>How is it possible ?
  (I ask it before made this change on all my big videos...)</p>
  <p>Mediainfo output for 40GB video :</p>
  <pre><code>General
  Unique ID                                : 238228999256890016546824715230238210616 (0xB3393C800F190F03AD96939C4A7BFA38)
  Complete name                            : C:\Users\xxx\Desktop\Inception.mkv
  Format                                   : Matroska
  Format version                           : Version 4
  File size                                : 30.9 GiB
  Duration                                 : 2 h 28 min
  Overall bit rate mode                    : Variable
  Overall bit rate                         : 29.9 Mb/s
  Movie name                               : Inception 2010 Blu-ray Remux 1080p VC-1 DTS-HD MA 5.1-HomeTheater
  Encoded date                             : UTC 2017-09-03 16:37:28
  Writing application                      : mkvmerge v14.0.0 ('Flow') 64bit
  Writing library                          : libebml v1.3.4 + libmatroska v1.4.5
  
  Video
  ID                                       : 1
  Format                                   : VC-1
  Format profile                           : Advanced@L3
  Codec ID                                 : V_MS/VFW/FOURCC / WVC1
  Codec ID/Hint                            : Microsoft
  Duration                                 : 2 h 28 min
  Bit rate                                 : 24.0 Mb/s
  Width                                    : 1 920 pixels
  Height                                   : 1 080 pixels
  Display aspect ratio                     : 16:9
  Frame rate mode                          : Constant
  Frame rate                               : 23.976 (24000/1001) FPS
  Color space                              : YUV
  Chroma subsampling                       : 4:2:0
  Bit depth                                : 8 bits
  Scan type                                : Progressive
  Compression mode                         : Lossy
  Bits/(Pixel*Frame)                       : 0.483
  Stream size                              : 24.8 GiB (80%)
  Title                                    : VC-1 / 24014 kbps / 1080p / 23,976 fps / 16:9 / Advanced Profile 3
  Default                                  : Yes
  Forced                                   : No
  
  Audio #1
  ID                                       : 2
  Format                                   : DTS XLL
  Format/Info                              : Digital Theater Systems
  Commercial name                          : DTS-HD Master Audio
  Codec ID                                 : A_DTS
  Duration                                 : 2 h 28 min
  Bit rate mode                            : Variable
  Bit rate                                 : 3 689 kb/s
  Channel(s)                               : 6 channels
  Channel layout                           : C L R Ls Rs LFE
  Sampling rate                            : 48.0 kHz
  Frame rate                               : 93.750 FPS (512 SPF)
  Bit depth                                : 24 bits
  Compression mode                         : Lossless
  Stream size                              : 3.82 GiB (12%)
  Title                                    : DTS-HD MA / 5.1 / 48 kHz / 3689 kbps / 24-bit
  Language                                 : English
  Default                                  : No
  Forced                                   : No
  
  Audio #2
  ID                                       : 4
  Format                                   : AC-3
  Format/Info                              : Audio Coding 3
  Commercial name                          : Dolby Digital
  Codec ID                                 : A_AC3
  Duration                                 : 2 h 28 min
  Bit rate mode                            : Constant
  Bit rate                                 : 640 kb/s
  Channel(s)                               : 6 channels
  Channel layout                           : L R C LFE Ls Rs
  Sampling rate                            : 48.0 kHz
  Frame rate                               : 31.250 FPS (1536 SPF)
  Compression mode                         : Lossy
  Stream size                              : 678 MiB (2%)
  Title                                    : VFF AC3 5.1
  Language                                 : French
  Service kind                             : Complete Main
  Default                                  : Yes
  Forced                                   : No
  
  Audio #3
  ID                                       : 5
  Format                                   : DTS
  Format/Info                              : Digital Theater Systems
  Codec ID                                 : A_DTS
  Duration                                 : 2 h 28 min
  Bit rate mode                            : Constant
  Bit rate                                 : 1 509 kb/s
  Channel(s)                               : 6 channels
  Channel layout                           : C L R Ls Rs LFE
  Sampling rate                            : 48.0 kHz
  Frame rate                               : 93.750 FPS (512 SPF)
  Bit depth                                : 24 bits
  Compression mode                         : Lossy
  Stream size                              : 1.56 GiB (5%)
  Title                                    : VO DTS 5.1
  Language                                 : English
  Default                                  : No
  Forced                                   : No
  
  Text #1
  ID                                       : 3
  Format                                   : PGS
  Muxing mode                              : zlib
  Codec ID                                 : S_HDMV/PGS
  Codec ID/Info                            : Picture based subtitle format used on BDs/HD-DVDs
  Duration                                 : 2 h 27 min
  Bit rate                                 : 32.7 kb/s
  Count of elements                        : 3482
  Stream size                              : 34.4 MiB (0%)
  Title                                    : SDH
  Language                                 : English
  Default                                  : No
  Forced                                   : No
  
  Text #2
  ID                                       : 6
  Format                                   : UTF-8
  Codec ID                                 : S_TEXT/UTF8
  Codec ID/Info                            : UTF-8 Plain Text
  Duration                                 : 2 h 26 min
  Bit rate                                 : 0 b/s
  Count of elements                        : 5
  Stream size                              : 111 Bytes (0%)
  Title                                    : Forces
  Language                                 : French
  Default                                  : Yes
  Forced                                   : Yes
  
  Text #3
  ID                                       : 7
  Format                                   : UTF-8
  Codec ID                                 : S_TEXT/UTF8
  Codec ID/Info                            : UTF-8 Plain Text
  Duration                                 : 2 h 26 min
  Bit rate                                 : 46 b/s
  Count of elements                        : 1741
  Stream size                              : 50.2 KiB (0%)
  Title                                    : Complets
  Language                                 : French
  Default                                  : No
  Forced                                   : No
  </code></pre>
  <p>Mediainfo output for 2GB video :</p>
  <pre><code>General
  Complete name                            : C:\Users\xxxx\Desktop\Inception-1.m4v
  Format                                   : MPEG-4
  Format profile                           : Base Media / Version 2
  Codec ID                                 : mp42 (isom/iso2/avc1/mp41)
  File size                                : 2.84 GiB
  Duration                                 : 2 h 28 min
  Overall bit rate                         : 2 746 kb/s
  Movie name                               : Inception 2010 Blu-ray Remux 1080p VC-1 DTS-HD MA 5.1-HomeTheater
  Encoded date                             : UTC 2020-06-14 09:28:20
  Tagged date                              : UTC 2020-06-14 09:28:20
  Writing application                      : HandBrake 1.3.2 2020050300
  
  Video
  ID                                       : 1
  Format                                   : AVC
  Format/Info                              : Advanced Video Codec
  Format profile                           : Main@L4
  Format settings                          : CABAC / 4 Ref Frames
  Format settings, CABAC                   : Yes
  Format settings, Reference frames        : 4 frames
  Codec ID                                 : avc1
  Codec ID/Info                            : Advanced Video Coding
  Duration                                 : 2 h 28 min
  Bit rate                                 : 2 579 kb/s
  Width                                    : 1 920 pixels
  Height                                   : 800 pixels
  Display aspect ratio                     : 2.40:1
  Frame rate mode                          : Variable
  Frame rate                               : 23.976 (24000/1001) FPS
  Minimum frame rate                       : 23.974 FPS
  Maximum frame rate                       : 23.981 FPS
  Color space                              : YUV
  Chroma subsampling                       : 4:2:0
  Bit depth                                : 8 bits
  Scan type                                : Progressive
  Bits/(Pixel*Frame)                       : 0.070
  Stream size                              : 2.67 GiB (94%)
  Writing library                          : x264 core 157 r2935 545de2f
  Encoding settings                        : cabac=1 / ref=2 / deblock=1:0:0 / analyse=0x1:0x111 / me=hex / subme=6 / psy=1 / psy_rd=1.00:0.00 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=1 / 8x8dct=0 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=-2 / threads=12 / lookahead_threads=2 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / bluray_compat=0 / constrained_intra=0 / bframes=3 / b_pyramid=2 / b_adapt=1 / b_bias=0 / direct=1 / weightb=1 / open_gop=0 / weightp=1 / keyint=240 / keyint_min=24 / scenecut=40 / intra_refresh=0 / rc_lookahead=30 / rc=crf / mbtree=1 / crf=22.0 / qcomp=0.60 / qpmin=0 / qpmax=69 / qpstep=4 / vbv_maxrate=20000 / vbv_bufsize=25000 / crf_max=0.0 / nal_hrd=none / filler=0 / ip_ratio=1.40 / aq=1:1.00
  Encoded date                             : UTC 2020-06-14 09:28:20
  Tagged date                              : UTC 2020-06-14 09:28:20
  Color range                              : Limited
  Color primaries                          : BT.709
  Transfer characteristics                 : BT.709
  Matrix coefficients                      : BT.709
  Codec configuration box                  : avcC
  
  Audio
  ID                                       : 2
  Format                                   : AAC LC
  Format/Info                              : Advanced Audio Codec Low Complexity
  Codec ID                                 : mp4a-40-2
  Duration                                 : 2 h 28 min
  Bit rate mode                            : Constant
  Bit rate                                 : 161 kb/s
  Channel(s)                               : 2 channels
  Channel layout                           : L R
  Sampling rate                            : 48.0 kHz
  Frame rate                               : 46.875 FPS (1024 SPF)
  Compression mode                         : Lossy
  Stream size                              : 170 MiB (6%)
  Title                                    : DTS-HD MA / 5.1 / 48 kHz / 3689 kbps / 24-bit
  Language                                 : English
  Default                                  : Yes
  Alternate group                          : 1
  Encoded date                             : UTC 2020-06-14 09:28:20
  Tagged date                              : UTC 2020-06-14 09:28:20
  </code></pre>
  
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2020-06-25T11:54:09.947Z
Comments.Text: Please elaborate on what you mean with 40Go and 2Go - I found nothing like this with google...
Comments.UserDisplayName: Florian Claaßen
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2020-06-25T13:57:52.743Z
Comments.Text: Sorry, it is Giga Byte (GB), "Go" is in french. I edit OP.
Comments.UserDisplayName: geo667
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2020-06-25T16:03:50.457Z
Comments.Text: The basics of video compression is a pretty broad topic. There are whole books on it. It is also hard for us to say what was changed without knowing what your source video was and what your Handbrake settings were. (You can post the full text mode output from [MediaInfo] (https://mediaarea.net/en/MediaInfo) for the source info). Can you narrow your question down or post additional information?
Comments.UserDisplayName: Michael Liebman
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2020-06-25T17:04:05.040Z
Comments.Text: Thanks for your answer, I edit OP with mediainfo information
Comments.UserDisplayName: geo667
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2020-06-30T18:45:17.360Z
Comments.Text: I noticed that the Handbrake MP4 is a different size and aspect ratio than the original -- 800px high instead of 1080px. That would make it a little smaller and lower quality too.
Comments.UserDisplayName: bigO
Tags: <handbrake>
Title: what handbrake influences to get its results
UserDisplayName: geo667
ThreadText: # what handbrake influences to get its results
  
  (Asked by: username_0 on 2020-06-25)
  
  I have used handbrake on a 40GB video.
  I only have choosed mp4 format and launched the work.
  After few hours of work, I obtain a 2GB video, with same quality...
  
  How is it possible ?
  (I ask it before made this change on all my big videos...)
  
  Mediainfo output for 40GB video :
  
  ```
  General
  Unique ID                                : 238228999256890016546824715230238210616 (0xB3393C800F190F03AD96939C4A7BFA38)
  Complete name                            : C:\Users\xxx\Desktop\Inception.mkv
  Format                                   : Matroska
  Format version                           : Version 4
  File size                                : 30.9 GiB
  Duration                                 : 2 h 28 min
  Overall bit rate mode                    : Variable
  Overall bit rate                         : 29.9 Mb/s
  Movie name                               : Inception 2010 Blu-ray Remux 1080p VC-1 DTS-HD MA 5.1-HomeTheater
  Encoded date                             : UTC 2017-09-03 16:37:28
  Writing application                      : mkvmerge v14.0.0 ('Flow') 64bit
  Writing library                          : libebml v1.3.4 + libmatroska v1.4.5
  
  Video
  ID                                       : 1
  Format                                   : VC-1
  Format profile                           : Advanced@L3
  Codec ID                                 : V_MS/VFW/FOURCC / WVC1
  Codec ID/Hint                            : Microsoft
  Duration                                 : 2 h 28 min
  Bit rate                                 : 24.0 Mb/s
  Width                                    : 1 920 pixels
  Height                                   : 1 080 pixels
  Display aspect ratio                     : 16:9
  Frame rate mode                          : Constant
  Frame rate                               : 23.976 (24000/1001) FPS
  Color space                              : YUV
  Chroma subsampling                       : 4:2:0
  Bit depth                                : 8 bits
  Scan type                                : Progressive
  Compression mode                         : Lossy
  Bits/(Pixel*Frame)                       : 0.483
  Stream size                              : 24.8 GiB (80%)
  Title                                    : VC-1 / 24014 kbps / 1080p / 23,976 fps / 16:9 / Advanced Profile 3
  Default                                  : Yes
  Forced                                   : No
  
  Audio #1
  ID                                       : 2
  Format                                   : DTS XLL
  Format/Info                              : Digital Theater Systems
  Commercial name                          : DTS-HD Master Audio
  Codec ID                                 : A_DTS
  Duration                                 : 2 h 28 min
  Bit rate mode                            : Variable
  Bit rate                                 : 3 689 kb/s
  Channel(s)                               : 6 channels
  Channel layout                           : C L R Ls Rs LFE
  Sampling rate                            : 48.0 kHz
  Frame rate                               : 93.750 FPS (512 SPF)
  Bit depth                                : 24 bits
  Compression mode                         : Lossless
  Stream size                              : 3.82 GiB (12%)
  Title                                    : DTS-HD MA / 5.1 / 48 kHz / 3689 kbps / 24-bit
  Language                                 : English
  Default                                  : No
  Forced                                   : No
  
  Audio #2
  ID                                       : 4
  Format                                   : AC-3
  Format/Info                              : Audio Coding 3
  Commercial name                          : Dolby Digital
  Codec ID                                 : A_AC3
  Duration                                 : 2 h 28 min
  Bit rate mode                            : Constant
  Bit rate                                 : 640 kb/s
  Channel(s)                               : 6 channels
  Channel layout                           : L R C LFE Ls Rs
  Sampling rate                            : 48.0 kHz
  Frame rate                               : 31.250 FPS (1536 SPF)
  Compression mode                         : Lossy
  Stream size                              : 678 MiB (2%)
  Title                                    : VFF AC3 5.1
  Language                                 : French
  Service kind                             : Complete Main
  Default                                  : Yes
  Forced                                   : No
  
  Audio #3
  ID                                       : 5
  Format                                   : DTS
  Format/Info                              : Digital Theater Systems
  Codec ID                                 : A_DTS
  Duration                                 : 2 h 28 min
  Bit rate mode                            : Constant
  Bit rate                                 : 1 509 kb/s
  Channel(s)                               : 6 channels
  Channel layout                           : C L R Ls Rs LFE
  Sampling rate                            : 48.0 kHz
  Frame rate                               : 93.750 FPS (512 SPF)
  Bit depth                                : 24 bits
  Compression mode                         : Lossy
  Stream size                              : 1.56 GiB (5%)
  Title                                    : VO DTS 5.1
  Language                                 : English
  Default                                  : No
  Forced                                   : No
  
  Text #1
  ID                                       : 3
  Format                                   : PGS
  Muxing mode                              : zlib
  Codec ID                                 : S_HDMV/PGS
  Codec ID/Info                            : Picture based subtitle format used on BDs/HD-DVDs
  Duration                                 : 2 h 27 min
  Bit rate                                 : 32.7 kb/s
  Count of elements                        : 3482
  Stream size                              : 34.4 MiB (0%)
  Title                                    : SDH
  Language                                 : English
  Default                                  : No
  Forced                                   : No
  
  Text #2
  ID                                       : 6
  Format                                   : UTF-8
  Codec ID                                 : S_TEXT/UTF8
  Codec ID/Info                            : UTF-8 Plain Text
  Duration                                 : 2 h 26 min
  Bit rate                                 : 0 b/s
  Count of elements                        : 5
  Stream size                              : 111 Bytes (0%)
  Title                                    : Forces
  Language                                 : French
  Default                                  : Yes
  Forced                                   : Yes
  
  Text #3
  ID                                       : 7
  Format                                   : UTF-8
  Codec ID                                 : S_TEXT/UTF8
  Codec ID/Info                            : UTF-8 Plain Text
  Duration                                 : 2 h 26 min
  Bit rate                                 : 46 b/s
  Count of elements                        : 1741
  Stream size                              : 50.2 KiB (0%)
  Title                                    : Complets
  Language                                 : French
  Default                                  : No
  Forced                                   : No
  
  ```
  
  Mediainfo output for 2GB video :
  
  ```
  General
  Complete name                            : C:\Users\xxxx\Desktop\Inception-1.m4v
  Format                                   : MPEG-4
  Format profile                           : Base Media / Version 2
  Codec ID                                 : mp42 (isom/iso2/avc1/mp41)
  File size                                : 2.84 GiB
  Duration                                 : 2 h 28 min
  Overall bit rate                         : 2 746 kb/s
  Movie name                               : Inception 2010 Blu-ray Remux 1080p VC-1 DTS-HD MA 5.1-HomeTheater
  Encoded date                             : UTC 2020-06-14 09:28:20
  Tagged date                              : UTC 2020-06-14 09:28:20
  Writing application                      : HandBrake 1.3.2 2020050300
  
  Video
  ID                                       : 1
  Format                                   : AVC
  Format/Info                              : Advanced Video Codec
  Format profile                           : Main@L4
  Format settings                          : CABAC / 4 Ref Frames
  Format settings, CABAC                   : Yes
  Format settings, Reference frames        : 4 frames
  Codec ID                                 : avc1
  Codec ID/Info                            : Advanced Video Coding
  Duration                                 : 2 h 28 min
  Bit rate                                 : 2 579 kb/s
  Width                                    : 1 920 pixels
  Height                                   : 800 pixels
  Display aspect ratio                     : 2.40:1
  Frame rate mode                          : Variable
  Frame rate                               : 23.976 (24000/1001) FPS
  Minimum frame rate                       : 23.974 FPS
  Maximum frame rate                       : 23.981 FPS
  Color space                              : YUV
  Chroma subsampling                       : 4:2:0
  Bit depth                                : 8 bits
  Scan type                                : Progressive
  Bits/(Pixel*Frame)                       : 0.070
  Stream size                              : 2.67 GiB (94%)
  Writing library                          : x264 core 157 r2935 545de2f
  Encoding settings                        : cabac=1 / ref=2 / deblock=1:0:0 / analyse=0x1:0x111 / me=hex / subme=6 / psy=1 / psy_rd=1.00:0.00 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=1 / 8x8dct=0 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=-2 / threads=12 / lookahead_threads=2 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / bluray_compat=0 / constrained_intra=0 / bframes=3 / b_pyramid=2 / b_adapt=1 / b_bias=0 / direct=1 / weightb=1 / open_gop=0 / weightp=1 / keyint=240 / keyint_min=24 / scenecut=40 / intra_refresh=0 / rc_lookahead=30 / rc=crf / mbtree=1 / crf=22.0 / qcomp=0.60 / qpmin=0 / qpmax=69 / qpstep=4 / vbv_maxrate=20000 / vbv_bufsize=25000 / crf_max=0.0 / nal_hrd=none / filler=0 / ip_ratio=1.40 / aq=1:1.00
  Encoded date                             : UTC 2020-06-14 09:28:20
  Tagged date                              : UTC 2020-06-14 09:28:20
  Color range                              : Limited
  Color primaries                          : BT.709
  Transfer characteristics                 : BT.709
  Matrix coefficients                      : BT.709
  Codec configuration box                  : avcC
  
  Audio
  ID                                       : 2
  Format                                   : AAC LC
  Format/Info                              : Advanced Audio Codec Low Complexity
  Codec ID                                 : mp4a-40-2
  Duration                                 : 2 h 28 min
  Bit rate mode                            : Constant
  Bit rate                                 : 161 kb/s
  Channel(s)                               : 2 channels
  Channel layout                           : L R
  Sampling rate                            : 48.0 kHz
  Frame rate                               : 46.875 FPS (1024 SPF)
  Compression mode                         : Lossy
  Stream size                              : 170 MiB (6%)
  Title                                    : DTS-HD MA / 5.1 / 48 kHz / 3689 kbps / 24-bit
  Language                                 : English
  Default                                  : Yes
  Alternate group                          : 1
  Encoded date                             : UTC 2020-06-14 09:28:20
  Tagged date                              : UTC 2020-06-14 09:28:20
  
  ```
  
  **Tags:** handbrake
  
  > **Comments:**
  > **username_1**: Please elaborate on what you mean with 40Go and 2Go - I found nothing like this with google...  
  > **username_0**: Sorry, it is Giga Byte (GB), "Go" is in french. I edit OP.  
  > **username_2**: The basics of video compression is a pretty broad topic. There are whole books on it. It is also hard for us to say what was changed without knowing what your source video was and what your Handbrake settings were. (You can post the full text mode output from [MediaInfo] (https://mediaarea.net/en/MediaInfo) for the source info). Can you narrow your question down or post additional information?  
  > **username_0**: Thanks for your answer, I edit OP with mediainfo information  
  > **username_3**: I noticed that the Handbrake MP4 is a different size and aspect ratio than the original -- 800px high instead of 1080px. That would make it a little smaller and lower quality too.  
  
  ---
  
  ## 1 answers
  
  ### Answer by username_4 on 2020-06-26. Score: 1 | Accepted answer
  
  Input and output video formats are from the same generation (similar quality for similar bitrate). Handbrake default settings are prioritizing smaller size over better quality. Video bitrate is divided by 10, which is seriously impacting quality. Not so much because input is strongly standardized (Blu-ray) and Blu-ray tools are not optimized, but 2.5 Mbps is still low for HD, recommended bitrate for HD compressed in AVC are more around 5-10 Mbps.
  
  Input and output audio formats are very different, input is lossless and output is lossy compressed, not speaking about the channel count (from 5.1 to stereo). This is a serious loss, and not speaking about the trashed French track...
  
  Input subtitles tracks are not big, but trashed.
  
  You say "with same quality", which is totally wrong (for both video and 1st audio), and some data is completely lost (2nd audio track + all subtitle tracks). The right sentence is "with a quality I accept for personal reasons". If all the quality and data loss is acceptable for you (for example you plan to only watch this film on your laptop during a noisy travel, and never on a big TV with a 5.1 soundbar in a quite room), go for it, else tweak Handbrake e.g. at the minimum for a not too bad experience on TV+soundbar 5 Mbps video + 5.1 512 kbps AAC for both audio tracks + copy of subtitle tracks (for 2nd audio and all subtitles: if you don't want to trash them, else it is fine to trash them). This would lead to a 6 GB file in your case.
  
  > **Comments:**
  > **username_0**: Thank you very much for this very qualitative response! I will follow your advice.  
  > **username_0**: Sorry, I have another question : what mean cursor named "Constant Quality" in Handbrake (Video tab) : when I use your recommended configuration and a value of 23 for it, I have only a 2,5GB video. 23 is the recommended value for hight definition source say the documentation. I don't understand how to use this parameter.  
  > **username_4**: You can have a global overview of of this settings on e.g. https://slhck.info/video/2017/02/24/crf-guide.html , and 23 is usually OK, here if you have such small file with this setting it may just need that your video content is easy to compress, it may do a bigger file with another content (the quality is constant, not the file size). You may try a lower value for better quality, e.g. 20. Handbrake recommends 20-24 for HD https://handbrake.fr/docs/en/latest/workflow/adjust-quality.html.  
  > **username_0**: Thanks username_4 !  
  
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