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• Nexus One

  19 mars 2010, par Mans — Uncategorized

  I have had a Nexus One for about a week (thanks Google), and naturally I have an opinion or two about it.
  

  Hardware

  With the front side dominated by a touch-screen and a lone, round button, the Nexus One appearance is similar to that of most contemporary smartphones. The reverse sports a 5 megapixel camera with LED flash, a Google logo, and a smaller HTC logo. Power button, volume control, and headphone and micro-USB sockets are found along the edges. It is with appreciation I note the lack of a front-facing camera ; the silly idea of video calls is finally put to rest.

  Powering up the phone (I’m beginning to question the applicability of that word), I am immediately enamoured with the display. At 800×480 pixels, the AMOLED display is crystal-clear and easily viewable even in bright light. In a darker environment, the display automatically dims. The display does have one quirk in that the subpixel pattern doesn’t actually have a full RGB triplet for each pixel. The close-up photo below shows the pattern seen when displaying a solid white colour.

  

  The result of this is that fine vertical lines, particularly red or blue ones, look a bit jagged. Most of the time this is not much of a problem, and I find it an acceptable compromise for the higher effective resolution it provides.

  Basic interaction

  The Android system is by now familiar, and the Nexus offers no surprises in basic usage. All the usual applications come pre-installed : browser, email, calendar, contacts, maps, and even voice calls. Many of the applications integrate with a Google account, which is nice. Calendar entries, map placemarks, etc. are automatically shared between desktop and mobile. Gone is the need for the bug-ridden custom synchronisation software with which mobile phones of the past were plagued.

  Launching applications is mostly speedy, and recently used apps are kept loaded as long as memory needs allow. Although this garbage-collection-style of application management, where you are never quite sure whether an app is still running, takes a few moments of acclimatisation, it works reasonably well in day to day use. Most of the applications are well-behaved and save their data before terminating.

  Email

  Two email applications are included out of the box : one generic and one Gmail-only. As I do not use Gmail, I cannot comment on this application. The generic email client supports IMAP, but is rather limited in functionality. Fortunately, a much-enhanced version, K-9, is available for download. The main feature I find lacking here is threaded message view.

  The features, or lack thereof, in the email applications is not, however, of huge importance, as composing email, or any longer piece of text, is something one rather avoids on a system like this. The on-screen keyboard, while falling among the better of its kind, is still slow to use. Lack of tactile feedback means accidentally tapping the wrong key is easily done, and entering numbers or punctuation is an outright chore.

  Browser

  Whatever the Nexus lacks in email abilities, it makes up for with the browser. Surfing the web on a phone has never been this pleasant. Page rendering is quick, and zooming is fast and simple. Even pages not designed for mobile viewing are easy to read with smart reformatting almost entirely eliminating the sideways scrolling which hampered many a mobile browser of old.

  Calls and messaging

  Being a phone, the Nexus One is obviously able to make and receive calls, and it does so with ease. Entering a number or locating a stored contact are both straight-forward operations. During a call, audio is clear and of adequate loudness, although I have yet to use the phone in really noisy surroundings.

  The other traditional task of a mobile phone, messaging, is also well-supported. There isn’t really much to say about this.

  Multimedia

  Having a bit of an interest in most things multimedia, I obviously tested the capabilities of the Nexus by throwing some assorted samples at it, revealing ample space for improvement. With video limited to H.264 and MPEG4, and the only supported audio codecs being AAC, MP3, Vorbis, and AMR, there are many files which will not play.

  To make matters worse, only selected combinations of audio and video will play together. Several video files I tested played without sound, yet when presented with the very same audio data alone, it was correctly decoded. As for container formats, it appears restricted to MP4/MOV, and Ogg (for Vorbis). AVI files are recognised as media files, but I was unable to find an AVI file which would play.

  With a device clearly capable of so much more, the poor multimedia support is nothing short of embarrassing.

  The Market

  Much of the hype surrounding Android revolves around the Market, Google’s virtual marketplace for app authors to sell or give away their creations. The thousands of available applications are broadly categorised, and a search function is available.

  The categorised lists are divided into free and paid sections, while search results, disappointingly, are not. To aid the decision, ratings and comments are displayed alongside the summary and screenshots of each application. Overall, the process of finding and installing an application is mostly painless. While it could certainly be improved, it could also have been much worse.

  The applications themselves are, as hinted above, beyond numerous. Sadly, quality does not quite match up to quantity. The vast majority of the apps are pointless, though occasionally mildly amusing, gimmicks of no practical value. The really good ones, and they do exist, are very hard to find unless one knows precisely what to look for.

  Battery

  Packing great performance into a pocket-size device comes with a price in battery life. The battery in the Nexus lasts considerably shorter time than that in my older, less feature-packed Nokia phone. To some extent this is probably a result of me actually using it a lot more, yet the end result is the same : more frequent recharging. I should probably get used to the idea of recharging the phone every other night.

  Verdict

  The Nexus One is a capable hardware platform running an OS with plenty of potential. The applications are still somewhat lacking (or very hard to find), although the basic features work reasonably well. Hopefully future Android updates will see more and better core applications integrated, and I imagine that over time, I will find third-party apps to solve my problems in a way I like. I am not putting this phone on the shelf just yet.

• FFMPEG sound not playing in video converted from audio in browsers (chrome/firefox) except safari

  7 février 2019, par Bhavik Rathod

  Sound not playing in Video (mp4) converted from Audio (mp3), Below is my code

  I am using FFMPEG version 4.1

  ffmpeg -y -loop 1 -i background.jpg -i dia.mp3 -c:v libx264 -tune stillimage -pix_fmt yuv420p -c:a ac3_fixed -b:a 128k -shortest -vf "[in]drawtext=text=Hi:x=(w-text_w)/2:y=(h-text_h):fontfile=arial.ttf:fontsize=100:fontcolor=ffffff:alpha='if(lt(t,9.2763066666667),0,if(lt(t,9.2763066666667+1),(t-9.2763066666667)/1,if(lt(t,12.83428),1,if(lt(t,12.83428+1),(1-(t-12.83428))/1,0))))'" output.mp4 2>&1

  I have tried putting -movflags +faststart as an output option

  I am using ac3_fixed because i found that fix for handle memory management, My server is getting hang on using aac no video created nothing i have to restart instance to get back to work. by using ac3_fixed everything is perfect but issue is only sound playing in chrome and firefox.

  Below is full log while using aac

  `ffmpeg version 4.1-static https://johnvansickle.com/ffmpeg/  Copyright (c) 2000-2018 the FFmpeg developers
  
    built with gcc 6.3.0 (Debian 6.3.0-18+deb9u1) 20170516
  
    configuration: --enable-gpl --enable-version3 --enable-static --disable-debug --disable-ffplay --disable-indev=sndio --disable-outdev=sndio --cc=gcc-6 --enable-fontconfig --enable-frei0r --enable-gnutls --enable-gray --enable-libaom --enable-libfribidi --enable-libass --enable-libvmaf --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-librubberband --enable-libsoxr --enable-libspeex --enable-libvorbis --enable-libopus --enable-libtheora --enable-libvidstab --enable-libvo-amrwbenc --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzimg
  
    libavutil      56. 22.100 / 56. 22.100
  
    libavcodec     58. 35.100 / 58. 35.100
  
    libavformat    58. 20.100 / 58. 20.100
  
    libavdevice    58.  5.100 / 58.  5.100
  
    libavfilter     7. 40.101 /  7. 40.101
  
    libswscale      5.  3.100 /  5.  3.100
  
    libswresample   3.  3.100 /  3.  3.100
  
    libpostproc    55.  3.100 / 55.  3.100
  
  Input #0, image2, from '/var/www/html/xxxxx/assets/media/guest/e0ce3bfdab4b305d00459328afb94ca6.jpg':
  
    Duration: 00:00:00.04, start: 0.000000, bitrate: 196382 kb/s
  
      Stream #0:0: Video: mjpeg, yuvj444p(pc, bt470bg/unknown/unknown), 1920x1080 [SAR 1:1 DAR 16:9], 25 fps, 25 tbr, 25 tbn, 25 tbc
  
  [mp3 @ 0x5970440] Estimating duration from bitrate, this may be inaccurate
  
  Input #1, mp3, from '/var/www/html/xxxxx/assets/media/guest/e0ce3bfdab4b305d00459328afb94ca6.mp3':
  
    Metadata:
  
      title           : In the Cafe
  
      album           : British Council
  
      genre           : Blues
  
    Duration: 00:01:02.77, start: 0.000000, bitrate: 128 kb/s
  
      Stream #1:0: Audio: mp3, 44100 Hz, stereo, fltp, 128 kb/s
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (mjpeg (native) -> h264 (libx264))
  
    Stream #1:0 -> #0:1 (mp3 (mp3float) -> aac (native))
  
  Press [q] to stop, [?] for help
  
  [swscaler @ 0x5b91ec0] deprecated pixel format used, make sure you did set range correctly
  
  [libx264 @ 0x598e640] using SAR=1/1
  
  [libx264 @ 0x598e640] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 BMI2 AVX2
  
  [libx264 @ 0x598e640] profile High, level 4.0, 4:2:0, 8-bit
  
  [libx264 @ 0x598e640] 264 - core 157 r2935 545de2f - H.264/MPEG-4 AVC codec - Copyleft 2003-2018 - http://www.videolan.org/x264.html - options: cabac=1 ref=3 deblock=1:-3:-3 analyse=0x3:0x113 me=hex subme=7 psy=1 psy_rd=2.00:0.70 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-4 threads=1 lookahead_threads=1 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=crf mbtree=1 crf=23.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.20
  
  Output #0, mp4, to '/var/www/html/xxxxx/assets/media/guest/created_video/e0ce3bfdab4b305d00459328afb94ca6.mp4':
  
    Metadata:
  
      encoder         : Lavf58.20.100
  
      Stream #0:0: Video: h264 (libx264) (avc1 / 0x31637661), yuv420p(progressive), 1920x1080 [SAR 1:1 DAR 16:9], q=-1--1, 25 fps, 12800 tbn, 25 tbc
  
      Metadata:
  
        encoder         : Lavc58.35.100 libx264
  
      Side data:
  
        cpb: bitrate max/min/avg: 0/0/0 buffer size: 0 vbv_delay: -1
  
      Stream #0:1: Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 128 kb/s
  
      Metadata:
  
        encoder         : Lavc58.35.100 aac
  
  frame=   14 fps=0.0 q=0.0 size=       0kB time=00:00:00.00 bitrate=N/A speed=   frame=   28 fps= 27 q=0.0 size=       0kB time=00:00:00.00 bitrate=N/A speed=   frame=   42 fps= 27 q=28.0 size=       0kB time=00:00:00.00 bitrate=N/A speed=  frame=   44 fps= 21 q=28.0 size=     256kB time=00:00:00.02 bitrate=72266.5kbitsframe=   49 fps= 19 q=28.0 size=     256kB time=00:00:00.20 bitrate=10323.8kbitsframe=   55 fps= 18 q=28.0 size=     256kB time=00:00:00.48 bitrate=4353.4kbits/frame=   62 fps= 17 q=28.0 size=     256kB time=00:00:00.72 bitrate=2890.7kbits/frame=   68 fps= 16 q=28.0 size=     256kB time=00:00:01.00 bitrate=2088.6kbits/    
  
  `

• FFMPEG-jpg sequence to H.264 generate best result

  18 octobre 2015, par Ziki

  I have a jpg sequence which I need to convert to mp4, and I need to get the best result.

  As I understood, I need to supply the ’ffmpeg’ cmdln the following : bitrate, minrate, maxrate and bufsize.

  The only thing that I found about calculating the above params, is if I have the final output file size. But considering I want the best quality, I don’t know the final output file size, and I don’t care what it will be.

  Of course I have the framerate and the total frames.

  Here’s my ffmpeg cmdln :

  ffmpeg 
  
  -r 24 
  
  -start_number 0 
  
  -i "C:\pathToSequence\%06d.jpg" 
  
  -c copy 
  
  -vframes 792 
  
  -threads 16 
  
  -pix_fmt yuv420p 
  
  -c:v libx264 
  
  "C:\pathToOutput\result.mp4"

  The total size of the sequence is 128MB, 792 frames, 24 framerate, resolution 1280x720.

  Until now I used to add the following to the ffmpeg cmdln :

  -b:v 10000k -minrate 10000k -maxrate 10000k -bufsize 10000k

  And if it was 1080p :

  -b:v 20000k -minrate 20000k -maxrate 20000k -bufsize 20000k

  And I figured that if I put the max value that ffmpeg can handle (2147480) it will generate almost the same result as the above. But I think it’s a bad approach(correct me if I’m wrong).

  So if I need to get the best result, how do I calculate it(or I can simply put the max value) ?

  Also I would like if you have another helpful flags to add to make the best final result.

  —EDIT—

  Here’s the updated command :

  O:\tools\ffmpeg -framerate 24 -start_number 0 -i "C:\share\localProcess\test\%05d.jpg" -vframes 54 -pix_fmt yuv420p -c:v libx264 -preset veryslow -qp 1 "C:\share\localProcess\result\result.mp4"

  And this is the ouptout :

  ffmpeg version N-72383-g7206b94 Copyright (c) 2000-2015 the FFmpeg developers
  
    built with gcc 4.9.2 (GCC)
  
    configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-avisynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libdcadec --enable-libfreetype --enable-libgme --enable-libgsm --enable-libilbc --enable-libmodplug --enable-libmfx --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libschroedinger --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-aacenc --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --enable-lzma --enable-decklink --enable-zlib
  
    libavutil      54. 26.100 / 54. 26.100
  
    libavcodec     56. 41.100 / 56. 41.100
  
    libavformat    56. 33.101 / 56. 33.101
  
    libavdevice    56.  4.100 / 56.  4.100
  
    libavfilter     5. 16.101 /  5. 16.101
  
    libswscale      3.  1.101 /  3.  1.101
  
    libswresample   1.  1.100 /  1.  1.100
  
    libpostproc    53.  3.100 / 53.  3.100
  
  Input #0, image2, from 'C:\share\localProcess\test\%05d.jpg':
  
    Duration: 00:00:02.25, start: 0.000000, bitrate: N/A
  
      Stream #0:0: Video: mjpeg, yuvj444p(pc, bt470bg/unknown/unknown), 1280x720 [SAR 72:72 DAR 16:9], 24 fps, 24 tbr, 24 tbn, 24 tbc
  
  [swscaler @ 0000000004d6bf60] deprecated pixel format used, make sure you did set range correctly
  
  [libx264 @ 0000000004d7a9e0] using SAR=1/1
  
  [libx264 @ 0000000004d7a9e0] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 AVX2 LZCNT BMI2
  
  [libx264 @ 0000000004d7a9e0] profile High, level 5.0
  
  [libx264 @ 0000000004d7a9e0] 264 - core 146 r2538 121396c - H.264/MPEG-4 AVC codec - Copyleft 2003-2015 - http://www.videolan.org/x264.html - options: cabac=1 ref=16 deblock=1:0:0 analyse=0x3:0x133 me=umh subme=9 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=24 chroma_me=1 trellis=2 8x8dct=1 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=8 b_pyramid=2 b_adapt=2 b_bias=0 direct=3 weightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=24 scenecut=40 intra_refresh=0 rc=cqp mbtree=0 qp=1 ip_ratio=1.40 pb_ratio=1.30 aq=0
  
  Output #0, mp4, to 'C:\share\localProcess\result\result.mp4':
  
    Metadata:
  
      encoder         : Lavf56.33.101
  
      Stream #0:0: Video: h264 (libx264) ([33][0][0][0] / 0x0021), yuv420p, 1280x720 [SAR 1:1 DAR 16:9], q=-1--1, 24 fps, 12288 tbn, 24 tbc
  
      Metadata:
  
        encoder         : Lavc56.41.100 libx264
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (mjpeg (native) -> h264 (libx264))
  
  Press [q] to stop, [?] for help
  
  frame=   54 fps= 38 q=-1.0 Lsize=     542kB time=00:00:02.16 bitrate=2050.0kbits/s
  
  video:541kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.251171%
  
  [libx264 @ 0000000004d7a9e0] frame I:1     Avg QP: 0.00  size: 23629
  
  [libx264 @ 0000000004d7a9e0] frame P:22    Avg QP: 1.00  size: 16146
  
  [libx264 @ 0000000004d7a9e0] frame B:31    Avg QP: 2.81  size:  5623
  
  [libx264 @ 0000000004d7a9e0] consecutive B-frames: 16.7% 29.6% 16.7%  0.0%  9.3%  0.0% 13.0% 14.8%  0.0%
  
  [libx264 @ 0000000004d7a9e0] mb I  I16..4: 74.9% 20.2%  4.9%
  
  [libx264 @ 0000000004d7a9e0] mb P  I16..4:  0.3%  0.1%  1.2%  P16..4:  2.7%  0.4%  0.8%  0.2%  0.1%    skip:94.2%
  
  [libx264 @ 0000000004d7a9e0] mb B  I16..4:  0.0%  0.0%  0.0%  B16..8:  3.0%  0.4%  0.5%  direct: 0.3%  skip:95.7%  L0:56.0% L1:40.5% BI: 3.5%
  
  [libx264 @ 0000000004d7a9e0] 8x8 transform intra:16.5% inter:18.4%
  
  [libx264 @ 0000000004d7a9e0] direct mvs  spatial:54.8% temporal:45.2%
  
  [libx264 @ 0000000004d7a9e0] coded y,uvDC,uvAC intra: 33.9% 49.8% 49.5% inter: 1.3% 2.9% 2.9%
  
  [libx264 @ 0000000004d7a9e0] i16 v,h,dc,p: 79% 13%  4%  4%
  
  [libx264 @ 0000000004d7a9e0] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 12% 22% 48%  2%  4%  6%  3%  1%  2%
  
  [libx264 @ 0000000004d7a9e0] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 13% 13% 43%  5%  6%  4%  5%  5%  6%
  
  [libx264 @ 0000000004d7a9e0] i8c dc,h,v,p: 78% 12%  7%  3%
  
  [libx264 @ 0000000004d7a9e0] Weighted P-Frames: Y:0.0% UV:0.0%
  
  [libx264 @ 0000000004d7a9e0] ref P L0: 65.7%  2.4%  8.9%  4.5%  2.3%  3.0%  2.8%  3.9%  3.5%  0.8%  0.3%  0.5%  0.3%  0.5%  0.2%  0.3%
  
  [libx264 @ 0000000004d7a9e0] ref B L0: 76.9% 12.0%  3.4%  0.7%  3.6%  0.5%  2.1%  0.4%  0.1%  0.0%  0.1%  0.0%  0.1%  0.1%
  
  [libx264 @ 0000000004d7a9e0] ref B L1: 98.2%  1.8%
  
  [libx264 @ 0000000004d7a9e0] kb/s:1966.80

  Link to download JPG sequence.

  Link to download the result.