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• Adventures In NAS

  1er janvier, par Multimedia Mike — General

  In my post last year about my out-of-control single-board computer (SBC) collection which included my meager network attached storage (NAS) solution, I noted that :

  I find that a lot of my fellow nerds massively overengineer their homelab NAS setups. I’ll explore this in a future post. For my part, people tend to find my homelab NAS solution slightly underengineered.

  So here I am, exploring this is a future post. I’ve been in the home NAS game a long time, but have never had very elaborate solutions for such. For my part, I tend to take an obsessively reductionist view of what constitutes a NAS : Any small computer with a pool of storage and a network connection, running the Linux operating system and the Samba file sharing service.

  
  
  

  Many home users prefer to buy turnkey boxes, usually that allow you to install hard drives yourself, and then configure the box and its services with a friendly UI. My fellow weird computer nerds often buy cast-off enterprise hardware and set up more resilient, over-engineered solutions, as long as they have strategies to mitigate the noise and dissipate the heat, and don’t mind the electricity bills.

  If it works, awesome ! As an old hand at this, I am rather stuck in my ways, however, preferring to do my own stunts, both with the hardware and software solutions.

  My History With Home NAS Setups
  In 1998, I bought myself a new computer — beige box tower PC, as was the style as the time. This was when normal people only had one computer at most. It ran Windows, but I was curious about this new thing called “Linux” and learned to dual boot that. Later that year, it dawned on me that nothing prevented me from buying a second ugly beige box PC and running Linux exclusively on it. Further, it could be a headless Linux box, connected by ethernet, and I could consolidate files into a single place using this file sharing software named Samba.
  

  I remember it being fairly onerous to get Samba working in those days. And the internet was not quite so helpful in those days. I recall that the thing that blocked me for awhile was needing to know that I had to specify an entry for the Samba server machine in the LMHOSTS (Lanman hosts) file on the Windows 95 machine.

  However, after I cracked that code, I have pretty much always had some kind of ad-hoc home NAS setup, often combined with a headless Linux development box.

  In the early 2000s, I built a new beige box PC for a file server, with a new hard disk, and a coworker tutored me on setting up a (P)ATA UDMA 133 (or was it 150 ? anyway, it was (P)ATA’s last hurrah before SATA conquered all) expansion card and I remember profiling that the attached hard drive worked at a full 21 MBytes/s reading. It was pretty slick. Except I hadn’t really thought things through. You see, I had a hand-me-down ethernet hub cast-off from my job at the time which I wanted to use. It was a 100 Mbps repeater hub, not a switch, so the catch was that all connected machines had to be capable of 100 Mbps. So, after getting all of my machines (3 at the time) upgraded to support 10/100 ethernet (the old off-brand PowerPC running Linux was the biggest challenge), I profiled transfers and realized that the best this repeater hub could achieve was about 3.6 MBytes/s. For a long time after that, I just assumed that was the upper limit of what a 100 Mbps network could achieve. Obviously, I now know that the upper limit ought to be around 11.2 MBytes/s and if I had gamed out that fact in advance, I would have realized it didn’t make sense to care about super-fast (for the time) disk performance.

  At this time, I was doing a lot for development for MPlayer/xine/FFmpeg. I stored all of my multimedia material on this NAS. I remember being confused when I was working with Y4M data, which is raw frames, which is lots of data. xine, which employed a pre-buffering strategy, would play fine for a few seconds and then stutter. Eventually, I reasoned out that the files I was working with had a data rate about twice what my awful repeater hub supported, which is probably the first time I came to really understand and respect streaming speeds and their implications for multimedia playback.

  Smaller Solutions
  For a period, I didn’t have a NAS. Then I got an Apple AirPort Extreme, which I noticed had a USB port. So I bought a dual drive brick to plug into it and used that for a time. Later (2009), I had this thing called the MSI Wind Nettop which is the only PC I’ve ever seen that can use a CompactFlash (CF) card for a boot drive. So I did just that, and installed a large drive so it could function as a NAS, as well as a headless dev box. I’m still amazed at what a low-power I/O beast this thing is, at least when compared to all the ARM SoCs I have tried in the intervening 1.5 decades. I’ve had spinning hard drives in this thing that could read at 160 MBytes/s (‘dd’ method) and have no trouble saturating the gigabit link at 112 MBytes/s, all with its early Intel Atom CPU.

  Around 2015, I wanted a more capable headless dev box and discovered Intel’s line of NUCs. I got one of the fat models that can hold a conventional 2.5″ spinning drive in addition to the M.2 SATA SSD and I was off and running. That served me fine for a few years, until I got into the ARM SBC scene. One major limitation here is that 2.5″ drives aren’t available in nearly the capacities that make a NAS solution attractive.

  Current Solution
  My current NAS solution, chronicled in my last SBC post– the ODroid-HC2, which is a highly compact ARM SoC with an integrated USB3-SATA bridge so that a SATA drive can be connected directly to it :

  
  

  

  ODROID-HC2 NAS

  
  

  I tend to be weirdly proficient at recalling dates, so I’m surprised that I can’t recall when I ordered this and put it into service. But I’m pretty sure it was circa 2018. It’s only equipped with an 8 TB drive now, but I seem to recall that it started out with only a 4 TB drive. I think I upgraded to the 8 TB drive early in the pandemic in 2020, when ISPs were implementing temporary data cap amnesty and I was doing what a r/DataHoarder does.

  The HC2 has served me well, even though it has a number of shortcomings for a hardware set chartered for NAS :

  1. While it has a gigabit ethernet port, it’s documented that it never really exceeds about 70 MBytes/s, due to the SoC’s limitations
  2. The specific ARM chip (Samsung Exynos 5422 ; more than a decade old as of this writing) lacks cryptography instructions, slowing down encryption if that’s your thing (e.g., LUKS)
  3. While the SoC supports USB3, that block is tied up for the SATA interface ; the remaining USB port is only capable of USB2 speeds
  4. 32-bit ARM, which prevented me from running certain bits of software I wanted to try (like Minio)
  5. Only 1 drive, so no possibility for RAID (again, if that’s your thing)

  I also love to brag on the HC2’s power usage : I once profiled the unit for a month using a Kill-A-Watt and under normal usage (with the drive spinning only when in active use). The unit consumed 4.5 kWh… in an entire month.

  New Solution
  Enter the ODroid-HC4 (I purchased mine from Ameridroid but Hardkernel works with numerous distributors) :

  
  

  

  ODroid-HC4 with an SSD and a conventional drive

  
  

  I ordered this earlier in the year and after many months of procrastinating and obsessing over the best approach to take with its general usage, I finally have it in service as my new NAS. Comparing point by point with the HC2 :

  1. The gigabit ethernet runs at full speed (though a few things on my network run at 2.5 GbE now, so I guess I’ll always be behind)
  2. The ARM chip (Amlogic S905X3) has AES cryptography acceleration and handles all the LUKS stuff without breaking a sweat ; “cryptsetup benchmark” reports between 500-600 MBytes/s on all the AES variants
  3. The USB port is still only USB2, so no improvement there
  4. 64-bit ARM, which means I can run Minio to simulate block storage in a local dev environment for some larger projects I would like to undertake
  5. Supports 2 drives, if RAID is your thing

  How I Set It Up
  How to set up the drive configuration ? As should be apparent from the photo above, I elected for an SSD (500 GB) for speed, paired with a conventional spinning HDD (18 TB) for sheer capacity. I’m not particularly trusting of RAID. I’ve watched it fail too many times, on systems that I don’t even manage, not to mention that aforementioned RAID brick that I had attached to the Apple AirPort Extreme.

  I had long been planning to use bcache, the block caching interface for Linux, which can use the SSD as a speedy cache in front of the more capacious disk. There is also LVM cache, which is supposed to achieve something similar. And then I had to evaluate the trade-offs in whether I wanted write-back, write-through, or write-around configurations.

  This was all predicated on the assumption that the spinning drive would not be able to saturate the gigabit connection. When I got around to setting up the hardware and trying some basic tests, I found that the conventional HDD had no trouble keeping up with the gigabit data rate, both reading and writing, somewhat obviating the need for SSD acceleration using any elaborate caching mechanisms.

  Maybe that’s because I sprung for the WD Red Pro series this time, rather than the Red Plus ? I’m guessing that conventional drives do deteriorate over the years. I’ll find out.

  For the operating system, I stuck with my newest favorite Linux distro : DietPi. While HardKernel (parent of ODroid) makes images for the HC units, I had also used DietPi for the HC2 for the past few years, as it tends to stay more up to date.

  Then I rsync’d my data from HC2 -> HC4. It was only about 6.5 TB of total data but it took days as this WD Red Plus drive is only capable of reading at around 10 MBytes/s these days. Painful.

  For file sharing, I’m pretty sure most normal folks have nice web UIs in their NAS boxes which allow them to easily configure and monitor the shares. I know there are such applications I could set up. But I’ve been doing this so long, I just do a bare bones setup through the terminal. I installed regular Samba and then brought over my smb.conf file from the HC2. 1 by 1, I tested that each of the old shares were activated on the new NAS and deactivated on the old NAS. I also set up a new share for the SSD. I guess that will just serve as a fast I/O scratch space on the NAS.

  The conventional drive spins up and down. That’s annoying when I’m actively working on something but manage not to hit the drive for like 5 minutes and then an application blocks while the drive wakes up. I suppose I could set it up so that it is always running. However, I micro-manage this with a custom bash script I wrote a long time ago which logs into the NAS and runs the “date” command every 2 minutes, appending the output to a file. As a bonus, it also prints data rate up/down stats every 5 seconds. The spinning file (“nas-main/zz-keep-spinning/keep-spinning.txt”) has never been cleared and has nearly a quarter million lines. I suppose that implies that it has kept the drive spinning for 1/2 million minutes which works out to around 347 total days. I should compare that against the drive’s SMART stats, if I can remember how. The earliest timestamp in the file is from March 2018, so I know the HC2 NAS has been in service at least that long.

  For tasks, vintage cron still does everything I could need. In this case, that means reaching out to websites (like this one) and automatically backing up static files.

  I also have to have a special script for starting up. Fortunately, I was able to bring this over from the HC2 and tweak it. The data disks (though not boot disk) are encrypted. Those need to be unlocked and only then is it safe for the Samba and Minio services to start up. So one script does all that heavy lifting in the rare case of a reboot (this is the type of system that’s well worth having on a reliable UPS).

  Further Work
  I need to figure out how to use the OLED display on the NAS, and how to make it show something more useful than the current time and date, which is what it does in its default configuration with HardKernel’s own Linux distro. With DietPi, it does nothing by default. I’m thinking it should be able to show the percent usage of each of the 2 drives, at a minimum.

  I also need to establish a more responsible backup regimen. I’m way too lazy about this. Fortunately, I reason that I can keep the original HC2 in service, repurposed to accept backups from the main NAS. Again, I’m sort of micro-managing this since a huge amount of data isn’t worth backing up (remember the whole DataHoarder bit), but the most important stuff will be shipped off.

  The post Adventures In NAS first appeared on Breaking Eggs And Making Omelettes.

• Progress with rtc.io

  12 août 2014, par silvia

  At the end of July, I gave a presentation about WebRTC and rtc.io at the WDCNZ Web Dev Conference in beautiful Wellington, NZ.

  

  Putting that talk together reminded me about how far we have come in the last year both with the progress of WebRTC, its standards and browser implementations, as well as with our own small team at NICTA and our rtc.io WebRTC toolbox.

  

  One of the most exciting opportunities is still under-exploited : the data channel. When I talked about the above slide and pointed out Bananabread, PeerCDN, Copay, PubNub and also later WebTorrent, that’s where I really started to get Web Developers excited about WebRTC. They can totally see the shift in paradigm to peer-to-peer applications away from the Server-based architecture of the current Web.

  Many were also excited to learn more about rtc.io, our own npm nodules based approach to a JavaScript API for WebRTC.

  

  We believe that the World of JavaScript has reached a critical stage where we can no longer code by copy-and-paste of JavaScript snippets from all over the Web universe. We need a more structured module reuse approach to JavaScript. Node with JavaScript on the back end really only motivated this development. However, we’ve needed it for a long time on the front end, too. One big library (jquery anyone ?) that does everything that anyone could ever need on the front-end isn’t going to work any longer with the amount of functionality that we now expect Web applications to support. Just look at the insane growth of npm compared to other module collections :

  

  For those that – like myself – found it difficult to understand how to tap into the sheer power of npm modules as a font end developer, simply use browserify. npm modules are prepared following the CommonJS module definition spec. Browserify works natively with that and “compiles” all the dependencies of a npm modules into a single bundle.js file that you can use on the front end through a script tag as you would in plain HTML. You can learn more about browserify and module definitions and how to use browserify.

  For those of you not quite ready to dive in with browserify we have prepared prepared the rtc module, which exposes the most commonly used packages of rtc.io through an “RTC” object from a browserified JavaScript file. You can also directly download the JavaScript file from GitHub.

  

  So, I hope you enjoy rtc.io and I hope you enjoy my slides and large collection of interesting links inside the deck, and of course : enjoy WebRTC ! Thanks to Damon, JEeff, Cathy, Pete and Nathan – you’re an awesome team !

  On a side note, I was really excited to meet the author of browserify, James Halliday (@substack) at WDCNZ, whose talk on “building your own tools” seemed to take me back to the times where everything was done on the command-line. I think James is using Node and the Web in a way that would appeal to a Linux Kernel developer. Fascinating !!

  The post Progress with rtc.io first appeared on ginger’s thoughts.

• FFMPEG : RTSP re-stream dies randomly

  14 mai 2018, par stevendesu

  I have a security camera streaming RTSP, and I wish to re-stream this to an RTMP ingest server. For now I’m using my laptop as an ffmpeg proxy, but eventually I’ll use a raspberry pi or something similar (cheap/small)

  Here’s the command I’m using (pretty simple) :

  ffmpeg -i rtsp://@10.0.0.16:554/1/h264major -c:v libx264 -c:a none -f flv rtmp://output/camera_stream

  This works but after a minute or two the stream dies. Here’s the output :

  ffmpeg version N-90057-g7c82e0f Copyright (c) 2000-2018 the FFmpeg developers
  
    built with gcc 5.4.0 (Ubuntu 5.4.0-6ubuntu1~16.04.6) 20160609
  
    configuration: --prefix=/home/sbarnett/ffmpeg_build --pkg-config-flags=--static --extra-cflags=-I/home/sbarnett/ffmpeg_build/include --extra-ldflags=-L/home/sbarnett/ffmpeg_build/lib --extra-libs='-lpthread -lm' --bindir=/home/sbarnett/bin --enable-gpl --enable-libass --enable-libfdk-aac --enable-libfreetype --enable-libmp3lame --enable-libopus --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --enable-libspeex --enable-nonfree
  
    libavutil      56.  7.101 / 56.  7.101
  
    libavcodec     58. 11.101 / 58. 11.101
  
    libavformat    58.  9.100 / 58.  9.100
  
    libavdevice    58.  1.100 / 58.  1.100
  
    libavfilter     7. 12.100 /  7. 12.100
  
    libswscale      5.  0.101 /  5.  0.101
  
    libswresample   3.  0.101 /  3.  0.101
  
    libpostproc    55.  0.100 / 55.  0.100
  
  Input #0, rtsp, from 'rtsp://@10.0.0.16:554/1/h264major':
  
    Metadata:
  
      title           : h264major
  
      comment         : h264major
  
    Duration: N/A, start: 0.360000, bitrate: N/A
  
      Stream #0:0: Video: h264 (Main), yuvj420p(pc, bt709, progressive), 720x480, 25 fps, 25 tbr, 90k tbn, 50 tbc
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (h264 (native) -> h264 (libx264))
  
  Press [q] to stop, [?] for help
  
  [libx264 @ 0x38843c0] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 BMI2 AVX2
  
  [libx264 @ 0x38843c0] profile High, level 3.0
  
  [libx264 @ 0x38843c0] 264 - core 155 - H.264/MPEG-4 AVC codec - Copyleft 2003-2018 - http://www.videolan.org/x264.html - options: cabac=1 ref=3 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=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=1:1.00
  
  Output #0, flv, to 'rtmp://output/camera_stream':
  
    Metadata:
  
      title           : h264major
  
      comment         : h264major
  
      encoder         : Lavf58.9.100
  
      Stream #0:0: Video: h264 (libx264) ([7][0][0][0] / 0x0007), yuvj420p(pc), 720x480, q=-1--1, 25 fps, 1k tbn, 25 tbc
  
      Metadata:
  
        encoder         : Lavc58.11.101 libx264
  
      Side data:
  
        cpb: bitrate max/min/avg: 0/0/0 buffer size: 0 vbv_delay: -1
  
  Past duration 0.999992 too large
  
      Last message repeated 29 times
  
  [rtsp @ 0x3847600] max delay reached. need to consume packet
  
  [rtsp @ 0x3847600] RTP: missed 48 packets
  
  Past duration 0.999992 too large
  
      Last message repeated 4 times
  
  frame=   44 fps=0.0 q=0.0 size=       0kB time=00:00:00.00 bitrate=N/A dup=0 drop=5 speed=   0x    
  
  frame=   57 fps= 54 q=28.0 size=      43kB time=00:00:00.16 bitrate=2186.4kbits/s dup=0 drop=5 speed=0.153x    
  
  ... (lots of similar messages) ...   
  
  frame= 1163 fps= 26 q=28.0 size=    1341kB time=00:00:44.84 bitrate= 245.0kbits/s dup=0 drop=5 speed=0.99x    
  
  frame= 1177 fps= 26 q=28.0 size=    1353kB time=00:00:45.40 bitrate= 244.2kbits/s dup=0 drop=5 speed=0.99x    
  
  [rtsp @ 0x3847600] max delay reached. need to consume packet
  
  [rtsp @ 0x3847600] RTP: missed 2 packets
  
  frame= 1190 fps= 26 q=28.0 size=    1370kB time=00:00:45.92 bitrate= 244.4kbits/s dup=0 drop=5 speed=0.99x    
  
  [h264 @ 0x38c08c0] Increasing reorder buffer to 1
  
  frame= 1201 fps= 26 q=28.0 size=    1381kB time=00:00:46.36 bitrate= 244.0kbits/s dup=0 drop=5 speed=0.989x    
  
  frame= 1214 fps= 26 q=28.0 size=    1393kB time=00:00:46.88 bitrate= 243.4kbits/s dup=0 drop=5 speed=0.989x    
  
  ... (lots of similar messages) ...    
  
  frame= 1761 fps= 25 q=28.0 size=    2030kB time=00:01:08.80 bitrate= 241.7kbits/s dup=0 drop=5 speed=0.993x    
  
  frame= 1774 fps= 25 q=28.0 size=    2041kB time=00:01:09.32 bitrate= 241.2kbits/s dup=0 drop=5 speed=0.993x    
  
  [flv @ 0x3884900] Failed to update header with correct duration.
  
  [flv @ 0x3884900] Failed to update header with correct filesize.
  
  frame= 1782 fps= 25 q=-1.0 Lsize=    2127kB time=00:01:11.64 bitrate= 243.2kbits/s dup=0 drop=5 speed=1.02x    
  
  video:2092kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 1.679417%
  
  [libx264 @ 0x38843c0] frame I:8     Avg QP:16.89  size: 42446
  
  [libx264 @ 0x38843c0] frame P:1672  Avg QP:19.54  size:  1065
  
  [libx264 @ 0x38843c0] frame B:102   Avg QP:23.00  size:   205
  
  [libx264 @ 0x38843c0] consecutive B-frames: 92.4%  0.0%  0.0%  7.6%
  
  [libx264 @ 0x38843c0] mb I  I16..4: 12.9% 36.2% 50.9%
  
  [libx264 @ 0x38843c0] mb P  I16..4:  0.2%  0.2%  0.0%  P16..4: 16.7%  0.7%  1.0%  0.0%  0.0%    skip:81.1%
  
  [libx264 @ 0x38843c0] mb B  I16..4:  0.1%  0.1%  0.0%  B16..8: 11.7%  0.1%  0.0%  direct: 1.5%  skip:86.5%  L0:62.2% L1:35.3% BI: 2.5%
  
  [libx264 @ 0x38843c0] 8x8 transform intra:40.8% inter:47.4%
  
  [libx264 @ 0x38843c0] coded y,uvDC,uvAC intra: 46.5% 53.0% 17.2% inter: 3.9% 8.7% 0.0%
  
  [libx264 @ 0x38843c0] i16 v,h,dc,p: 21% 56%  8% 15%
  
  [libx264 @ 0x38843c0] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 23% 33% 31%  1%  2%  3%  2%  2%  3%
  
  [libx264 @ 0x38843c0] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 25% 39%  9%  3%  3%  4%  5%  3%  8%
  
  [libx264 @ 0x38843c0] i8c dc,h,v,p: 43% 33% 21%  3%
  
  [libx264 @ 0x38843c0] Weighted P-Frames: Y:0.0% UV:0.0%
  
  [libx264 @ 0x38843c0] ref P L0: 88.0%  1.4%  6.6%  4.0%
  
  [libx264 @ 0x38843c0] ref B L0: 99.4%  0.5%  0.1%
  
  [libx264 @ 0x38843c0] ref B L1: 99.4%  0.6%
  
  [libx264 @ 0x38843c0] kb/s:238.73

  The camera is pretty cheap (from China) so it’s likely I’m getting bad data from it or it’s cutting out for a few seconds at a time. Ideally I would need ffmpeg to handle this well (ignore bad data, wait as long as necessary for good data to resume encoding)

  Using ffplay to check out the RTSP stream, I get output like the following :

  $> ffplay -i rtsp://@10.0.0.16:554/1/h264major
  
  ffplay version N-90057-g7c82e0f Copyright (c) 2003-2018 the FFmpeg developers
  
    built with gcc 5.4.0 (Ubuntu 5.4.0-6ubuntu1~16.04.6) 20160609
  
    configuration: --prefix=/home/sbarnett/ffmpeg_build --pkg-config-flags=--static --extra-cflags=-I/home/sbarnett/ffmpeg_build/include --extra-ldflags=-L/home/sbarnett/ffmpeg_build/lib --extra-libs='-lpthread -lm' --bindir=/home/sbarnett/bin --enable-gpl --enable-libass --enable-libfdk-aac --enable-libfreetype --enable-libmp3lame --enable-libopus --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --enable-libspeex --enable-nonfree
  
    libavutil      56.  7.101 / 56.  7.101
  
    libavcodec     58. 11.101 / 58. 11.101
  
    libavformat    58.  9.100 / 58.  9.100
  
    libavdevice    58.  1.100 / 58.  1.100
  
    libavfilter     7. 12.100 /  7. 12.100
  
    libswscale      5.  0.101 /  5.  0.101
  
    libswresample   3.  0.101 /  3.  0.101
  
    libpostproc    55.  0.100 / 55.  0.100
  
  Input #0, rtsp, from 'rtsp://@10.0.0.16:554/1/h264major':0B f=0/0
  
    Metadata:
  
      title           : h264major
  
      comment         : h264major
  
    Duration: N/A, start: 0.320000, bitrate: N/A
  
      Stream #0:0: Video: h264 (Main), yuvj420p(pc, bt709, progressive), 720x480, 25 fps, 25 tbr, 90k tbn, 50 tbc
  
  [swscaler @ 0x7f6bbc093180] deprecated pixel format used, make sure you did set range correctly
  
  [rtsp @ 0x7f6bc0000940] max delay reached. need to consume packet
  
  [rtsp @ 0x7f6bc0000940] RTP: missed 2 packets
  
  [h264 @ 0x7f6bc0041080] error while decoding MB 44 28, bytestream -37
  
  [h264 @ 0x7f6bc0041080] concealing 95 DC, 95 AC, 95 MV errors in I frame
  
  [rtsp @ 0x7f6bc0000940] max delay reached. need to consume packet
  
  [rtsp @ 0x7f6bc0000940] RTP: missed 1 packets
  
  [h264 @ 0x7f6bc0041080] error while decoding MB 43 29, bytestream -49
  
  [h264 @ 0x7f6bc0041080] concealing 51 DC, 51 AC, 51 MV errors in I frame
  
  [rtsp @ 0x7f6bc0000940] max delay reached. need to consume packet
  
  [rtsp @ 0x7f6bc0000940] RTP: missed 2 packets
  
  [h264 @ 0x7f6bc0041080] Increasing reorder buffer to 1
  
  [rtsp @ 0x7f6bc0000940] max delay reached. need to consume packet
  
  [rtsp @ 0x7f6bc0000940] RTP: missed 3 packets
  
  [h264 @ 0x7f6bc02c3600] error while decoding MB 27 29, bytestream -24
  
  [h264 @ 0x7f6bc02c3600] concealing 67 DC, 67 AC, 67 MV errors in I frame
  
  [rtsp @ 0x7f6bc0000940] max delay reached. need to consume packet
  
  [rtsp @ 0x7f6bc0000940] RTP: missed 2 packets
  
  [rtsp @ 0x7f6bc0000940] max delay reached. need to consume packet
  
  [rtsp @ 0x7f6bc0000940] RTP: missed 42 packets
  
  [rtsp @ 0x7f6bc0000940] max delay reached. need to consume packet
  
  [rtsp @ 0x7f6bc0000940] RTP: missed 2 packets

  Then eventually the video just freezes. The first time it froze after around 5 minutes, but I wasn’t able to say definitively if it froze the instant 44 packets were dropped or if it froze randomly later. So the second time I stared intently.... for 21 minutes. Then I got bored of it not freezing, turned to pet my cat, and when I looked back 15 seconds later it was frozen. I think it only breaks when no one is watching it.

  What I can say definitively is :

  • While running normally, M-V hovers around 0 (anywhere between -0.01 and +0.01)
  • Once frozen, M-V begins to count down into negative numbers without stopping - although at a rate slower than -1 per second
  • While running normally, aq is 0KB and vq is a positive number (I think it was 30KB or so ?)
  • Once frozen, vq is also 0KB

  It’s a really cheap camera with a crummy power supply that goes out if you breathe on it, so it’s likely the camera is going temporarily offline during this time — but I’d like ffmpeg to wait out a timeout and resume streaming when it sees the camera again.