resize mkv ma...

[anonimodoc]

buongiorno a tutti,
vi espongo subito il mio problema.
ho tanti film .mkv a 1080p.
1h 30m di film prendono anche 14 gigabyte.
allora ho provato a trovare un modo per ridurre il formato.

ho preso un film d'animazione. ho tolto sottotitoli e audio che non mi interessavano con mkvmerge e questo è il rapporto di avinaptic:

[ About file ]

Name: Ortone e il mondo dei chi.mkv
Date: Thu, 15 Dec 2011 11:59:41 +0100
Size: 3,953,548,470 bytes (3770.397635 MiB)

[ Magic ]

Tipo file: data

[ Generic infos ]

Duration: 01:23:48 (5028.352 s)
Container: matroska
Production date: Thu, 15 Dec 2011 11:56:32 +0100
Total tracks: 2
Track nr. 1: audio (A_AC3) {ita}
Track nr. 2: video (V_MPEG4/ISO/AVC) {eng}
Muxing library: libebml v1.2.2 + libmatroska v1.3.0
Writing application: mkvmerge v5.0.1 ('Es ist Sommer') built on Oct 9 2011 11:55:43

[ Relevant data ]

Resolution: 1280 x 688
Width: multiple of 32
Height: multiple of 16
Average DRF: 18.779029
Standard deviation: 0.588104
Std. dev. weighted mean: 0.555019

[ Video track ]

Codec ID: V_MPEG4/ISO/AVC
Resolution: 1280 x 688
Frame aspect ratio: 80:43 = 1.860465 (~1.85:1)
Pixel aspect ratio: 1:1 = 1
Display aspect ratio: 80:43 = 1.860465 (~1.85:1)
Framerate: 23.975987 fps
Content encoding:
order: 0
scope: all frames
type: compression
compression algorithm: header stripping
stripped header: 1 bytes
Stream size: 3,550,545,449 bytes (3386.064004 MiB)
Duration (bs): 01:23:48 (5028.322754 s)
Bitrate (bs): 5648.874382 kbps
Qf: 0.267539

[ Audio track ]

Codec ID: A_AC3
Sampling frequency: 48000 Hz
Channels: 6
Content encoding:
order: 0
scope: all frames
type: compression
compression algorithm: header stripping
stripped header: 2 bytes
Stream size: 402,268,160 bytes (383.632813 MiB)
Bitstream type (bs): AC3
Frames (bs): 157,136
Duration (bs): 01:23:48 (5028.352 s)
Chunk-aligned (bs): Yes
Bitrate (bs): 640 kbps CBR
Sampling frequency (bs): 48000 Hz
Mode (bs): 3 front, 2 rear, 1 LFE

[ Video bitstream ]

Bitstream type: MPEG-4 Part 10
User data: x264 | core 112 r1834 a51816a | H.264/MPEG-4 AVC codec
User data: Copyleft 2003-2010 | http://www.videolan.org/x264.html | cabac=1
User data: ref=5 | deblock=1:-3:-3 | analyse=0x3:0x113 | me=umh | subme=7
User data: psy=1 | psy_rd=1.00:0.00 | mixed_ref=1 | me_range=16 | chroma_me=1
User data: trellis=1 | 8x8dct=1 | cqm=0 | deadzone=21,11 | fast_pskip=1
User data: chroma_qp_offset=-2 | threads=36 | sliced_threads=0 | nr=0
User data: decimate=1 | interlaced=0 | constrained_intra=0 | bframes=3
User data: b_pyramid=2 | b_adapt=2 | b_bias=0 | direct=1 | weightb=1
User data: open_gop=0 | weightp=2 | keyint=240 | keyint_min=23 | scenecut=40
User data: intra_refresh=0 | rc_lookahead=50 | rc=2pass | mbtree=1
User data: bitrate=5650 | ratetol=1.0 | qcomp=0.60 | qpmin=10 | qpmax=51
User data: qpstep=4 | cplxblur=20.0 | qblur=0.5 | ip_ratio=1.40 | aq=1:1.00
SPS id: 0
Profile: High@L4.1
Num ref frames: 5
Aspect ratio: Square pixels
Chroma format: YUV 4:2:0
PPS id: 0 (SPS: 0)
Entropy coding type: CABAC
Weighted prediction: P slices - explicit weighted prediction
Weighted bipred idc: B slices - implicit weighted prediction
8x8dct: Yes
Total frames: 120,559
Drop/delay frames: 0
Corrupt frames: 0

P-slices: 35608 ( 29.536 %) ######
B-slices: 83447 ( 69.217 %) ##############
I-slices: 1504 ( 1.248 %)
SP-slices: 0 ( 0.000 %)
SI-slices: 0 ( 0.000 %)

[ DRF analysis ]

average DRF: 18.779029
standard deviation: 0.588104
max DRF: 25

DRF<16: 0 ( 0.000 %)
DRF=16: 28 ( 0.023 %)
DRF=17: 1334 ( 1.107 %)
DRF=18: 31211 ( 25.889 %) #####
DRF=19: 81288 ( 67.426 %) #############
DRF=20: 6535 ( 5.421 %) #
DRF=21: 31 ( 0.026 %)
DRF=22: 13 ( 0.011 %)
DRF=23: 11 ( 0.009 %)
DRF=24: 5 ( 0.004 %)
DRF=25: 103 ( 0.085 %)
DRF>25: 0 ( 0.000 %)

P-slices average DRF: 18.810352
P-slices std. deviation: 0.612632
P-slices max DRF: 25

B-slices average DRF: 18.79617
B-slices std. deviation: 0.533109
B-slices max DRF: 25

I-slices average DRF: 17.086436
I-slices std. deviation: 0.406695
I-slices max DRF: 23

[ Profile compliancy ]

Selected profile: MTK PAL 6000
Resolution: 1280 x 688 > 720 x 576
Framerate: 23.975987 <> 25
Buffer underflow: 00:00:00 (frame 6)
Buffer underflow: 00:00:01 (frame 14)
Buffer underflow: 00:00:01 (frame 21)
Buffer underflow: 00:00:01 (frame 28)
Buffer underflow: 00:00:02 (frame 36)
Buffer underflow: 00:00:02 (frame 47)
Buffer underflow: 00:00:02 (frame 59)
Buffer underflow: 00:00:03 (frame 69)
Buffer underflow: 00:00:03 (frame 76)
Buffer underflow: 00:00:03 (frame 83)
Buffer underflow: 00:00:04 (frame 91)
Buffer underflow: 00:00:04 (frame 99)
Buffer underflow: 00:00:04 (frame 107)
Buffer underflow: 00:00:05 (frame 114)
Buffer underflow: 00:00:05 (frame 123)
Buffer underflow: 00:00:06 (frame 134)
Buffer underflow: 00:00:06 (frame 150)
Buffer underflow: 00:00:07 (frame 170)
Buffer underflow: 00:00:08 (frame 192)
Buffer underflow: 00:00:09 (frame 214)
Error: Too many violations

This report was created by AVInaptic (14-12-2011) on 16-12-2011 09:49:59

dopo di che per ridurre il formato l'ho passato in handbrake. senza modificare alcun settaggio. ho solo caricato il video e avviato l'encoding.

ecco il rapporto di avinaptic:

[ About file ]

Name: Ortone e il mondo dei chi.mkv
Date: Thu, 15 Dec 2011 22:32:06 +0100
Size: 1,403,421,129 bytes (1338.406686 MiB)

[ Magic ]

Tipo file: data

[ Generic infos ]

Duration: 01:23:48 (5028.3225 s)
Container: matroska
Total tracks: 2
Track nr. 1: video (V_MPEG4/ISO/AVC) {eng}
Track nr. 2: audio (A_AAC) {ita}
Muxing library: libmkv 0.6.4.1
Writing application: HandBrake 0.9.5

[ Relevant data ]

Resolution: 1280 x 688
Width: multiple of 32
Height: multiple of 16
Average DRF: 24.957805
Standard deviation: 0.353254
Std. dev. weighted mean: 0.00108

[ Video track ]

Codec ID: V_MPEG4/ISO/AVC
Resolution: 1280 x 688
Frame aspect ratio: 80:43 = 1.860465 (~1.85:1)
Pixel aspect ratio: 1:1 = 1
Display aspect ratio: 80:43 = 1.860465 (~1.85:1)
Framerate: 24 fps
Stream size: 1,298,852,340 bytes (1238.682117 MiB)
Duration (bs): 01:23:43 (5023.291586 s)
Bitrate (bs): 2068.527885 kbps
Qf: 0.09787

[ Audio track ]

Codec ID: A_AAC
Sampling frequency: 48000 Hz
Channels: 2
Stream size: 100,533,651 bytes (95.876361 MiB)
Bitstream type (bs): AAC LC (Low Complexity)
Frames (bs): 235,703
Duration (bs): 01:23:48 (5028.330667 s)
Chunk-aligned (bs): Yes
Bitrate (bs): 159.947557 kbps VBR
Sampling frequency (bs): 48000 Hz
Mode (bs): 2: front-left, front-right

[ Video bitstream ]

Bitstream type: MPEG-4 Part 10
User data: x264 | core 112 | H.264/MPEG-4 AVC codec | Copyleft 2003-2010
User data: http://www.videolan.org/x264.html | cabac=1 | ref=2 | deblock=1:0:0
User data: analyse=0x1:0x111 | me=hex | subme=6 | psy=1 | psy_rd=1.00:0.00
User data: mixed_ref=0 | me_range=16 | chroma_me=1 | trellis=0 | 8x8dct=0
User data: cqm=0 | deadzone=21,11 | fast_pskip=1 | chroma_qp_offset=-2
User data: threads=3 | sliced_threads=0 | nr=0 | decimate=1 | interlaced=0
User data: constrained_intra=0 | bframes=2 | b_pyramid=2 | b_adapt=1 | b_bias=0
User data: direct=1 | weightb=0 | open_gop=0 | weightp=2 | keyint=240
User data: keyint_min=24 | scenecut=40 | intra_refresh=0 | rc_lookahead=40
User data: rc=crf | mbtree=1 | crf=20.0 | qcomp=0.60 | qpmin=3 | qpmax=51
User data: qpstep=4 | ip_ratio=1.40 | aq=1:1.00
SPS id: 0
Profile: Main@L3.1
Num ref frames: 4
Aspect ratio: Square pixels
Chroma format: YUV 4:2:0
PPS id: 0 (SPS: 0)
Entropy coding type: CABAC
Weighted prediction: P slices - explicit weighted prediction
Weighted bipred idc: No
8x8dct: No
Total frames: 120,559
Drop/delay frames: 0
Corrupt frames: 0

P-slices: 50949 ( 42.261 %) ########
B-slices: 67913 ( 56.332 %) ###########
I-slices: 1697 ( 1.408 %)
SP-slices: 0 ( 0.000 %)
SI-slices: 0 ( 0.000 %)

[ DRF analysis ]

average DRF: 24.957805
standard deviation: 0.353254
max DRF: 25

DRF<22: 0 ( 0.000 %)
DRF=22: 1695 ( 1.406 %)
DRF=23: 1 ( 0.001 %)
DRF=24: 0 ( 0.000 %)
DRF=25: 118863 ( 98.593 %) ####################
DRF>25: 0 ( 0.000 %)

P-slices average DRF: 25
P-slices std. deviation: 0
P-slices max DRF: 25

B-slices average DRF: 25
B-slices std. deviation: 0
B-slices max DRF: 25

I-slices average DRF: 22.002357
I-slices std. deviation: 0.076728
I-slices max DRF: 25

[ Profile compliancy ]

Selected profile: MTK PAL 6000
Resolution: 1280 x 688 > 720 x 576
Framerate: 24 <> 25
Buffer underflow: 00:00:57 (frame 1364)
Buffer underflow: 00:00:57 (frame 1374)
Buffer underflow: 00:00:58 (frame 1384)
Buffer underflow: 00:00:58 (frame 1395)
Buffer underflow: 00:00:59 (frame 1406)
Buffer underflow: 00:00:59 (frame 1418)
Buffer underflow: 00:38:47 (frame 55846)
Buffer underflow: 00:38:50 (frame 55910)
Buffer underflow: 00:57:01 (frame 82098)
Buffer underflow: 00:57:02 (frame 82134)
Buffer underflow: 01:16:26 (frame 110056)
Buffer underflow: 01:16:27 (frame 110090)

This report was created by AVInaptic (14-12-2011) on 16-12-2011 09:45:15

vedendolo su pc e tv hd non noto alcuna differenza.
dal raporto avinaptic ho notato che ho perso 200 mega di audio ed il file muxato ha metà bitrate.

ma è mai possibile che a parità di qualità percepita ho ridotto ad 1/3 la dimensione del file?

inoltre con lo stesso procedimento ho ridotto una serie tv dove ogni puntata è di un giga a soli 110 mega a puntata. il rapporto è 1/10. anche qui la qualità è rimasta inalterata ed i codec utilizzati i medesimi.

dov'è sta l'inghippo???

vi prego aiutatemi a capire se non noto le differenze e dove ho sbagliato.
grazie

[Styb]

Prova a postare uno spezzone del file originale e del file ricodificato utilizzando un servizio di condivisione di file come ad es. MediaFire.
Gli spezzoni puoi prepararli anche con mkvmerge -> Globale -> Abilita suddivisione.

[anonimodoc]

ecco i link deigli spezzoni che mi hai chiesto:
spezzone di film originale
http://www.megaupload.com/?d=9IUU32Y8

spezzone di film muxato
http://www.megaupload.com/?d=YKXN8506

fatemi sapere.