3 Replies Latest reply: Jun 19, 2011 9:08 PM by shinsundo RSS

    HD Question

    waltercarlson

      I am interested in purchasing the Slingbox HD.  I see that 3 MPS is required.  Is that the upload and download speed requirement?  My internet provider gives me 1.5 or 2.0 MPS upload and my provider where I watch gives me 30 MPS download.  Can I still watch, but there may be some buffering involved or is HD viewing not possible at all?

        • Re: HD Question
          ArizonaSackbut Apprentice

          Hi Waltercalrson,

           

          If you can sustain 3 Mbps, it'll rock.  But you don't need that much bandwidth for Slingbox to work well and look nice.

           

          The network on the Slingbox side is where you need the upstream bandwidth since that's where the stream is being sent from.  The Player side needs downstream bandwidth since it's receiving, but your actual throughput will never be greater than whatever speed is available to the Slingbox.  The bottleneck is on the sending side.

           

          Network stability and congestion of course weighs into all of this, but the primary factor in determining overall viewing quality is the available upstream bandwidth at the Slingbox.

           

           

          There is a buffer involved.  Depending on which Player version you're using, there may be two.  There's always a streaming buffer, some Player versions also have a playback buffer (think local pause/rewind).

           

          Slingbox automatically manages the buffer(s) and streaming parameters based on sustainable throughput and the complexity of the video signal (for example, less motion on screen allows the system to use keyframe tricks to more efficiently use the available bandwidth).  These can be adjusted manually if you like, including the output resolution.   However, the auto system is quite good and extremely flexible.  When you see Optimizing... in the player, that's your clue that the auto system is actively adapting to current conditions.

           

           

          Throughput above 1 Mbps will be decent, more is noticeably better.  If you want to hit HD resolutions with top playback quality, 3+ Mbps is a realistic target.  Keep in mind that it's not an all-or-nothing deal though.  It'll make use of whatever it's given.

           

          Unless you tell it to do otherwise through manual adjustment, Slingbox will always stuff the highest quality picture it can sustain down whatever size pipe it's given.  It scales well and adjusts quickly.  If you can sustain 1.5 - 2 Mbps throughput, there's a good chance you'll be very happy with the results even if it slips below normal HD specs.

           

           

          It's my opinion that SlingMedia has a tendency to aim rather high when they publish their system requirements.  I'm not saying they're mistaken, just that those numbers are often for max quality/ideal conditions.  Given that, Slingbox can often perform quite well with more modest resources.

           

           

          Hope this helps,

           

          - Az

            • Re: HD Question
              shinsundo

              Thank you...very helpful...what does this translate to in kbps?

               

              I seem to get just over 8000 kpbs and picture is good.

               

              Cheers...so far, SB seems to be what I needed.

               

              Off topic, can the $50 extended warranty be purchased after the fact during the first 90 days?

               

              This thing gets hot and I gotta believe it won't last 3 years....

            • Re: HD Question
              eferz Expert

              Just to expand briefly...

              I am interested in purchasing the Slingbox HD.  I see that 3 MPS is  required.  Is that the upload and download speed requirement?  My  internet provider gives me 1.5 or 2.0 MPS upload and my provider where I  watch gives me 30 MPS download.  Can I still watch, but there may be  some buffering involved or is HD viewing not possible at all?

               

              Yes, the 3 Mbps requirement is required from both ends to sustain a HD quality feed.  However, the Slingbox will dynamically adjust the encoding resolution based on the quality of the connection to give you the best picture possible.

               

              This is an excerpt from the SBCore.sdb file which shows the supported resolutions.

               

              [VideoResolutionWAN]
              0=[No video]
              1=320 x 240
              2=160 x 120
              3=352 x 240
              4=176 x 120
              5=640 x 480
              6=640 x 240
              7=320 x 480
              8=128 x 096
              9=224 x 176
              10=448 x 240
              11=256 x 192
              12=1280 x 720
              13=1440 x 544
              14=1680 x 544
              15=1920 x 544
              16=1920 x 1080
              512=Auto