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  1. Hi, I have 2 video with the same content but different setting of codec; if I see the properties from mediaplayer classic I have the following:

    video 1

    Format : Matroska
    Format version : Version 1
    File size : 4.74 GiB
    Duration : 1h 53mn
    Overall bit rate mode : Variable
    Overall bit rate : 5 980 Kbps
    Encoded date : UTC 2013-04-16 01:27:30
    Writing library : WonderShare Matroska Muxer

    Video
    ID : 1
    Format : AVC
    Format/Info : Advanced Video Codec
    Format profile : Baseline@L3.1
    Format settings, CABAC : No
    Format settings, ReFrames : 1 frame
    Codec ID : V_MPEG4/ISO/AVC
    Duration : 1h 53mn
    Bit rate mode : Variable
    Bit rate : 5 541 Kbps
    Maximum bit rate : 8 473 Kbps
    Width : 1 280 pixels
    Height : 720 pixels
    Display aspect ratio : 16:9
    Frame rate mode : Constant
    Frame rate : 25.000 fps
    Color space : YUV
    Chroma subsampling : 4:2:0
    Bit depth : 8 bits
    Scan type : Progressive
    Bits/(Pixel*Frame) : 0.240
    Stream size : 4.39 GiB (93%)
    Default : Yes
    Forced : No

    Audio
    ID : 2
    Format : AC-3
    Format/Info : Audio Coding 3
    Mode extension : CM (complete main)
    Format settings, Endianness : Big
    Codec ID : A_AC3
    Duration : 1h 53mn
    Bit rate mode : Constant
    Bit rate : 320 Kbps
    Channel(s) : 2 channels
    Channel positions : Front: L R
    Sampling rate : 48.0 KHz
    Bit depth : 16 bits
    Compression mode : Lossy
    Delay relative to video : -40ms
    Stream size : 260 MiB (5%)
    Default : Yes
    Forced : No



    Video 2

    Format : Matroska
    Format version : Version 2
    File size : 1.18 GiB
    Duration : 1h 52mn
    Overall bit rate : 1 501 Kbps
    Encoded date : UTC 2013-04-16 05:41:27
    Writing application : mkvmerge v6.1.0 ('Old Devil') built on Mar 2 2013 14:32:37
    Writing library : libebml v1.3.0 + libmatroska v1.4.0

    Video
    ID : 1
    Format : AVC
    Format/Info : Advanced Video Codec
    Format profile : High@L3.1
    Format settings, CABAC : Yes
    Format settings, ReFrames : 4 frames
    Codec ID : V_MPEG4/ISO/AVC
    Duration : 1h 52mn
    Bit rate : 1 387 Kbps
    Width : 1 280 pixels
    Height : 720 pixels
    Display aspect ratio : 16:9
    Frame rate mode : Constant
    Frame rate : 25.000 fps
    Color space : YUV
    Chroma subsampling : 4:2:0
    Bit depth : 8 bits
    Scan type : Progressive
    Bits/(Pixel*Frame) : 0.060
    Stream size : 1.07 GiB (91%)
    Writing library : x264 core 130 r2273 b3065e6
    Encoding settings : cabac=1 / ref=3 / deblock=1:-1:-1 / analyse=0x3:0x113 / me=hex / subme=7 / psy=1 / psy_rd=1.00:0.15 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=1 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=-3 / 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=2 / keyint=250 / keyint_min=25 / scenecut=40 / intra_refresh=0 / rc_lookahead=40 / rc=2pass / mbtree=1 / bitrate=1387 / ratetol=1.0 / qcomp=0.60 / qpmin=0 / qpmax=69 / qpstep=4 / cplxblur=20.0 / qblur=0.5 / ip_ratio=1.40 / aq=1:1.00
    Default : Yes
    Forced : No

    Audio
    ID : 2
    Format : MPEG Audio
    Format version : Version 1
    Format profile : Layer 3
    Mode : Joint stereo
    Codec ID : A_MPEG/L3
    Codec ID/Hint : MP3
    Duration : 1h 52mn
    Bit rate mode : Constant
    Bit rate : 112 Kbps
    Channel(s) : 2 channels
    Sampling rate : 44.1 KHz
    Compression mode : Lossy
    Stream size : 90.1 MiB (7%)
    Language : Italian
    Default : Yes
    Forced : No

    when I see the video seem that "video 2" video quality is better then "video 1" video quality while audio seem to be the same while properties of codec are very different; can you help me to choose the version with better quality? if you want a small part of video I can host it...

    thx
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  2. You can't tell much about the quality by looking at codec settings. Unless you know the videos were the same before encoding. The only way to really judge the quality is to view the videos yourself.
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  3. Member
    Join Date: Feb 2010
    Location: England
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    Moreover, codec settings will not tell you if whoever encoded the video filtered it.
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  4. Member
    Join Date: Aug 2013
    Location: Central Germany
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    The first video is compressed with an AVC encoder which supports only the Baseline profile. This is a very simple part of the whole technology. It requires a lot more bitrate than an encoding in Main or High profile for a similar quality.
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  5. ok, I have understand, (however both video contain the same content recorded from the same broadcaster, but I don't know if the video are recorded both from digital satellite, terrestrial or one from satellite and the other from terrestrial; I see only that the video smaller seem to be better then the bigger and this is very strange)... Is very difficult for me choose because the quality is very similar...


    for the audio, both dvb-t that dvb-s standard use 48000 hz such frequency, there is a program where I can import stream audio of both and see the spectrum of the audio and choose the best? How can I make this?
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  6. Member
    Join Date: Feb 2010
    Location: England
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    Originally Posted by neo_rld View Post
    I see only that the video smaller seem to be better then the bigger and this is very strange)...
    Higher quality settings help video to compress, which would explain your observation. If you can't see much difference anyway, why do you care? Just pick the smaller one.
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  7. Member
    Join Date: Mar 2011
    Location: Nova Scotia, Canada
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    Video 1 was encoded with something called "WonderShare Matroska Muxer".

    I just looked at their site. I can't see anyone who actually knows anything about how to encode using it.

    Hence, #2 is probably better. That's my answer and I'm sticking to it.
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  8. Member
    Join Date: Aug 2013
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    Multiplexing is not encoding.
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  9. Originally Posted by LigH.de View Post
    The first video is compressed with an AVC encoder which supports only the Baseline profile. This is a very simple part of the whole technology. It requires a lot more bitrate than an encoding in Main or High profile for a similar quality.

    ok, I see that video2 has cabac coding,

    2)for the audio, what can you tell me? I think (but I'm not sure) that dvb-t and dvb-s (assuming that the 2 video are made from different digital transmission but I'm not sure also in this case) use frequency as 48000 hz and the audio in video 1 seem to be best of the audio in video 2...it's correct? if I convert a wav file both into file1 (mp3) and into file2 (ac3) setting to both to the same bitrate and to the same frequency,what is the file with the best quality?

    3)There is a mode to scan audio and view the better with sound spectrum?

    4)if I have an audio with a bitrate and frequency, and I encoding with a frequency and bitrate upper, I have the same quality of original files or can happen that the quality worse?
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  10. Originally Posted by LigH.de View Post
    Multiplexing is not encoding.
    yes, multiplexing is another thing

    I have written the broadcaster problem to answer jagabo that has write:
    "You can't tell much about the quality by looking at codec settings. Unless you know the videos were the same before encoding. The only way to really judge the quality is to view the videos yourself."

    I think that the video is the same before encoding, but my doubt is if are encoded with same settings both in dvb-s that dvb-t...
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  11. Originally Posted by Richard1485 View Post
    Originally Posted by neo_rld View Post
    I see only that the video smaller seem to be better then the bigger and this is very strange)...
    Higher quality settings help video to compress, which would explain your observation. If you can't see much difference anyway, why do you care? Just pick the smaller one.
    ok but I want understand also the audio, in the worse of the case I extract the audio from the "video1" and join with the video of "video2", else I delete video1 and keep video2...
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  12. You can use MMG to mux, mix/match video and audio streams. Beware, you may find the audio from one file doesn't really match the video from another file. Commercials, credits, lead-in logos may have been cut differently. Broadcasts in different countries can have different scenes cut. Etc.

    Spek, or Audacity with the ffmpeg source plugin, can import audio directly from almost any file and show you a the spectrum (though that's not the final arbiter of quality).
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  13. Member
    Join Date: Sep 2012
    Location: Australia
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    I think it's a mistake to judge the audio the way you're doing. As far as I can tell, Italian digital television audio is generally encoded using MPEG1. It's possible the first AC3 audio was re-encoded from the original, whereas the second may actually BE the original. Of course, AC3 transmission is possible, but at that bitrate??? You really ought to listen to them and judge them on how they sound, not their statistics.
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  14. Member
    Join Date: Feb 2010
    Location: England
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    I don't believe I've ever seen broadcast AC-3 with a bitrate other than 384kbps, regardless of whether it's 2.0 or 5.1.
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