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What is Micro-720p ripping method? I want to rip from 720p using ffmpeg and libx264.

Example m720p video information (I don't know the source video):

General
Complete name                            : D:\m720p.mp4
Format                                   : MPEG-4
Format profile                           : Base Media
Codec ID                                 : isom
File size                                : 596 MiB
Duration                                 : 1h 16mn
Overall bit rate mode                    : Variable
Overall bit rate                         : 1 096 Kbps
Encoded date                             : UTC 2013-02-05 23:44:15
Tagged date                              : UTC 2013-02-05 23:44:15

Video
ID                                       : 1
Format                                   : AVC
Format/Info                              : Advanced Video Codec
Format profile                           : High@L4.0
Format settings, CABAC                   : Yes
Format settings, ReFrames                : 9 frames
Codec ID                                 : avc1
Codec ID/Info                            : Advanced Video Coding
Duration                                 : 1h 16mn
Bit rate                                 : 1 003 Kbps
Maximum bit rate                         : 3 982 Kbps
Width                                    : 1 280 pixels
Height                                   : 688 pixels
Display aspect ratio                     : 1.85:1
Frame rate mode                          : Constant
Frame rate                               : 23.976 fps
Color space                              : YUV
Chroma subsampling                       : 4:2:0
Bit depth                                : 8 bits
Scan type                                : Progressive
Bits/(Pixel*Frame)                       : 0.048
Stream size                              : 542 MiB (91%)
Writing library                          : x264 core 129 r2230 1cffe9f
Encoding settings                        : cabac=1 / ref=9 / deblock=1:0:0 / analyse=0x3:0x113 / me=hex / subme=7 / psy=1 / psy_rd=1.00:0.00 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=1 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=-2 / threads=6 / lookahead_threads=1 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / bluray_compat=0 / constrained_intra=0 / bframes=8 / b_pyramid=2 / b_adapt=1 / b_bias=0 / direct=1 / weightb=1 / open_gop=0 / weightp=2 / keyint=240 / keyint_min=23 / scenecut=40 / intra_refresh=0 / rc_lookahead=40 / rc=2pass / mbtree=1 / bitrate=1003 / ratetol=1.0 / qcomp=0.60 / qpmin=10 / qpmax=51 / qpstep=4 / cplxblur=20.0 / qblur=0.5 / ip_ratio=1.40 / aq=1:1.00
Encoded date                             : UTC 2013-02-05 23:44:15
Tagged date                              : UTC 2013-02-05 23:44:24

Audio
ID                                       : 2
Format                                   : AAC
Format/Info                              : Advanced Audio Codec
Format profile                           : LC
Codec ID                                 : 40
Duration                                 : 1h 16mn
Bit rate mode                            : Variable
Bit rate                                 : 96.0 Kbps
Maximum bit rate                         : 130 Kbps
Channel(s)                               : 2 channels
Channel positions                        : Front: L R
Sampling rate                            : 48.0 KHz
Compression mode                         : Lossy
Stream size                              : 52.2 MiB (9%)
Language                                 : English
Encoded date                             : UTC 2013-02-05 23:44:22
Tagged date                              : UTC 2013-02-05 23:44:24
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Micro HD: 720p or 1080p at reducing the bitrate of the video quality loss. Better than DVDRip and BRRip quality. m720p size is getting smaller and lossless quality. example: size 1280x680, bitrate 1096, file size: 596 MiB.Exm video screen i.imgur.com/waRKWOS.jpg . Example video I found from the internet. Sorry, I know little english :) –  Ahmet KAPIKIRAN Feb 8 '13 at 20:34
    
I'm confident that a proper Blu-ray rip at 4 MBit/s offers better quality than a 720p rip squeezed down to 1 MBit/s. It won't be "lossless", probably not even visually "lossless". But I understand now what the "m-720p" refers to. Thanks for explaining. –  slhck Feb 8 '13 at 20:37
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2 Answers

up vote 0 down vote accepted

Slhck is right that Micro-720p is some pirated movie team's release type.

AFAIK, Those team are using some x264 encoding setting tunes to archiving low bit rates with acceptable quality. You can get what they've used from this line

Encoding settings                        : cabac=1 / ref=9 / deblock=1:0:0 / analyse=0x3:0x113 / me=hex / subme=7 / psy=1 / psy_rd=1.00:0.00 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=1 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=-2 / threads=6 / lookahead_threads=1 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / bluray_compat=0 / constrained_intra=0 / bframes=8 / b_pyramid=2 / b_adapt=1 / b_bias=0 / direct=1 / weightb=1 / open_gop=0 / weightp=2 / keyint=240 / keyint_min=23 / scenecut=40 / intra_refresh=0 / rc_lookahead=40 / rc=2pass / mbtree=1 / bitrate=1003 / ratetol=1.0 / qcomp=0.60 / qpmin=10 / qpmax=51 / qpstep=4 / cplxblur=20.0 / qblur=0.5 / ip_ratio=1.40 / aq=1:1.00

Most important settings for low bit-rates are: ref=9 subme=7 bframes=8

and deblock can be changed by -tune film|animation|grain

BTW, if you want trans-code audio to aac with ffmpeg, you should use lib_fdkaac, a far better codec than libfaac. Just try to got/complile a new ffmpeg with lib_fdcaac.

You can try some extreme setting with

ffmpeg -i 720p.mkv \
-c:v libx264 -crf 22 -preset slower -x264opts subme=11:ref=16:bframes=16 -tune film \
-c:a libfdk_aac -ac 2 -flags +qscale -global_quality 2 -afterburner 1 \
m720p.mp4

which I know give fair good results, but the video bit rates would be about 1400~1600 Kbps.

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that's not really a good answer. a good answer should explain how to solve a problem. This is difficult with the information you have given us. –  user 99572 is fine Mar 13 '13 at 8:51
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I guess I eventually found out where that term comes from—it's a pirated movie release type. It describes a 720p movie (thus, resized to 1280⨉720 pixels), but at a lower bit rate than what you'd usually need.

That's really no rocket science here. Calculating from those guidelines, the usual bit rate for a 720p Blu-ray rip would be around 4.5 MBit/s. One scene guide I found also uses 4 MBit/s for x264 encoding. So, in order to get a "micro" or "mini" 720p rip, you'd specify a lower bit rate.

You could do something like this:

ffmpeg -i in.mp4 -c:v libx264 -b:v 1M -c:a libfaac -q:a 100 out.mp4

Unfortunately, the default constant bit rate encoding mode in x264 is considered quite bad in terms of quality. Ideally you should do a two-pass encoding if you have the time. Here's an example with 1 MBit/s:

ffmpeg -y -i in.mp4 -c:v libx264 -preset slow -b:v 1M -pass 1 -an -f mp4 /dev/null
ffmpeg -i in.mp4 -c:v libx264 -preset slow -b:v 1M -pass 2 -c:a libfaac -q:a 100 out.mp4

You can change the preset from slow to ultraslow, or in the other direction to medium, fast, ultrafast. Choosing a slower preset gives you better compression at the cost of having to wait longer. Better compression means that the video will look better at the same file size.

Note that if your original file already contains a valid audio stream for MP4 (usually AAC or MP3 audio), then you can skip the -c:a libfaac -q:a 100 part and simply copy the bitstream with -c:a copy.

share|improve this answer
    
thank you for comment. I solved problem with second code. –  Ahmet KAPIKIRAN Feb 8 '13 at 21:00
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