user30076: 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


user12640: 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.

30076: <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>
 12640: <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>
