Transcoding 4K Media on the QNAP TS-251B NAS Plex Media Server?
Transcoding on a NAS such as the QNAP TS-251B device is the ability for a multimedia file to be changed from it’s existing format or codec to one that is better suited to the destination device. In this file access, the QNAP TS-251B NAS is the host device and the device you want to play the file is the client. This is the case of whether you are using Plex or not. Transcoding is typically required when a media file is more recently released than the client device that is accessing it, so the newer compression or playback format is unknown to the device you want to access it with. Alternatively, you want to access the movie or music on your QNAP TS-251B and do not want to use the original file in its full size. Transcoding can enable you to stream a much smaller version in weight or resolution if needed. IN a popular program such as PLEX, smooth playback is essential, and with the plex media server application on the QNAP TS-251B NAS using a larger percentage of CPU and Memory than most programs, it is very useful to know the plex transcoding abilities of any NAS.
Why should you factor transcoding with a Plex Media Server on a QNAP TS-251B NAS
When you install a Plex Media Server on your QNAP TS-251B, you should know that plex is not the answer to all of your media prayers. It has some limitations and depending on the NAS you use, these limits can be annoying. You will most likely have media files in a large collection of different formats and there is no guaranteeing that these are going to be compatible with TVs, iPads and Smartphones that you wish to watch them on. Although you will have a version of the Plex app on the viewing device, that app will still be locked to playback the supported media types on that device.
So if your phone does not support.MKV or .MOV, then neither does the plex app you installed on it. However, this is where transcoding comes in again, as the plex media server will use the NAS system resources to change the file to a version/format that it CAN play. What makes transcoding with Plex different to ordinary transcoding is that often, the NAS (in this case, the QNAP TS-251B) will not let the plex use the transcoding engine inside. This is not the end of the world, as it will use raw system power instead. The result is that where a regular transcode outside of plex will use 20-30%, in plex it could go as high as 70-80%. This is why it is important to know how well a plex NAS will transcode, as if it will hapen regularly, it could potentially slow down the general use of your QNAP TS-251B NAS.
Which plex supported client devices require transcoding from the QNAP TS-251B NAS
Destination devices range greatly and are often referred to as the client device. Common client devices that your QNAP TS-251B device will be accessed by are often:
- iPad or Android Tablet
- iPhone or Android Smartphone
- Smart TV or DLNA supported monitor
- Macbook, Laptop or Netbook device
- Sound systems such as Bose, Sonos and Sony DLNA systems
- Home Theatre Systems
- Network and internet-enabled gaming consoles such as PS4, Xbox One and Nvidia Shield
Transcoding between a QNAP TS-251B and your media can be of tremendous benefit for those with limited internet bandwidth, download limits or low powered devices whilst using the plex client application.
What are the Specifications of the QNAP TS-251B NAS?
The specifications for the QNAP TS-251B NAS are below and like all NAS devices, the CPU and Memory play a big part in how well it performs at transcoding both in and out of plex. The key factors to consider are if the device features an x86 or ARM-based CPU, does the QNAP TS-251B CPU feature a transcoding engine and how much RAM the device arrives with for multiple transcoding tasks. Below are the QNAP TS-251B specs:
IntelCeleron® J3355 Quad-Core
2.0 GHz (burst up to 2.5 GHz)
2 Year Warranty
TRANSCODING ENGINE: YES
1080P Support: YES
4K Support: YES
Transcoding Support: YES
Where to Buy
What is the difference between H.264 and H.265 4K Media on a NAS
H.264 and H.265 are common codecs of modern digital media. H264 is also referred to as AVC by experts (Advanced Video Coding) and is considered the standard for video file compression. This allows for media originally created for large-scale entertainment to be recording, compressed, and distributed to the home and smaller scale production of digital video content watched by you, the consumer via plex.
H265 is the newer and more consumer-friendly alternative to H264. It is also known as HEVC (High-Efficiency Video Coding) and was developed in order resolve issues of enormous 4K media files being just too large for your client device to playback. H.265 has become so popular and data saving that chances are that the YouTube clip, iTunes media or iPlayer content you watched was in .265 and HEVC. Typically a modern NAS such as the QNAP TS-251B will playback with JUST H.265 or it will PLayback both H.264 and H.265. The latter pretty much being exclusive to x86 or AMD based NAS CPU devices.
The QNAP TS-251B NAS 4K H.265 8-bit 30fps 46Mb/s PLEX Test 1- How well does it perform?
We pushed the QNAP TS-251B NAS to transcode a 4K H265 media file through the plex media server application. It was an 8-bit recording, running at 30 frames per second and featured a bitrate of 46 megabits per second. The QNAP TS-251B playback results were:
The QNAP TS-251B NAS 4K H.265 8-bit 25fps 38Mb/s PLEX Test 2 – How well does it perform?
Next, we pushed the QNAP TS-251B NAS to transcode a 4K H265 media file through the plex media server application. It was an 8-bit recording, but this time running at 25 frames per second and featured a bitrate of just 38 megabits per second. The QNAP TS-251B playback results were:
The QNAP TS-251B NAS 4K H.264 8-bit 30fps 51Mb/s PLEX Test 3 – How well does it perform?
Next, we pushed the QNAP TS-251B NAS to transcode a 4K H264 this time, the media file was an 8-bit recording, but this time back at 30 frames per second and featured a bitrate of 51 megabits per second, our highest yet. The QNAP TS-251B playback through the plex media server application results were:
The QNAP TS-251B NAS 4K H.265 10-bit 30fps 38Mb/s PLEX Test 7 – How well does it perform?
We then ran a much denser H.265 4K file on the QNAP TS-251B. This H265 file through the plex media server application was another 10-bit recording, at 30fps but this time with a much higher bitrate of 38 megabits per second. The QNAP TS-251B playback results were:
The QNAP TS-251B NAS 1080p H.265 8-bit 24fps 405kb/s PLEX Test 10 – How well does it perform?
In an effort to maintain fairness, we also covered an H.265 1080p file, so a comparison between this and Test 12 could be made. Ignore the test numerical order numbers, as this needed to be re-done (blame the QNAP TS-251B needing a firmware update mid transcode and therefore spoiled the results the first time). This was an HEVC/H265 8-bit file running at 24fps through the plex media server application, but with a comparatively low bitrate of just 405kbps. The results (correct this time) were again, fairly expected:
The QNAP TS-251B NAS Ultra HD 4K H.264 8-bit 24fps 22Mb/s PLEX Test 15 – How well does it perform?
We then decided to end on an older and currently more common owned 4K type of media file. This was kind of our control tests for most NAS and was no exception for the QNAP TS-251B through the plex media server application. This UHD file in 4K was an 8-Bit file, arriving in 24 frames per second and at a bitrate of 22megabits per second. For those who have owned 4k media for a while and want to consider their older H264 material, this test would be of interest. The results were.
The QNAP TS-251B NAS 1080p H.264 8-bit 24fps 13Mb/s PLEX Test 16 – How well does it perform?
In order to validate the earlier tests, we then switched back to 1080p/HD briefly as we could test an older h264 mp4 file via the plex media server application on the QNAP TS-251B. This 2014 made media file type was pretty high spec back then and below we can see how the QNAP TS-251B dealt with the 8-bit file at 24frames per second via plex with transcoding enabled.
The QNAP TS-251B NAS 4K H.265 10-bit 30fps 40Mb/s PLEX Test 18 – How well does it perform?
Satisfied with our testing 1080p, we decided to focus on 4K Media for this last three tests (Test 18, 19 and 20) as we wanted to introduce the same media file, but each time change just one variable, to see how the plex media server application on the QNAP TS-251B NAS coped. In all three tests we used a 10bit 4K H.265 Media file. But in test 18 we used the lowest bitrate, at 40Mb/s. Here is how PLEX on the ### transcoded.
The QNAP TS-251B NAS 4K H.265 10-bit 60fps 73Mb/s PLEX Test 20 – How well does it perform?
In test 20, I was starting to get sick of this file! So, i decided to keep a nice high bitrate version at 73Mb/s BUT then use a ramped up version at 60FPS. Sadly this file was only available in .MP4 rather than the .MKV that was used in test 18 and 19, so hopefully this does not undermine my QNAP TS-251B plex transcoding tests. Never the less this heavy h.265 4K file was punishing to the QNAP TS-251B NAS, or indeed ANY NAS.
The QNAP TS-251B NAS 720P H.265 8-bit 24fps MKV PLEX Test 21 – How well does it perform?
In order to start the testing on the QNAP TS-251B NAS properly, I started with a relatively modern and regular 720p resolution file. I did throw a few curveballs into the mix with an MKV file. Aside from that, this media file is fairly representative of the larger than average files you will encounter from time to time when choosing media taht is suitable for both larger and smaller devices. With the QNAP TS-251B plex media server, I was able to software transcode the file down to a manageable 480p (I wouldn’t dip below this on modern mobile devices unless you are on a strict data package). Though it did the job, the CPU use definitely was hogged by the QNAP TS-251B, as seen below:
Test File Type
- 720p Resolution
- HEVC Codec
- 24FPS Frame Rate
- 8 Bit Depth
- h.265 Compression
- MKV File Container
- 24p Video Frame Rate
The QNAP TS-251B NAS 1080P H.264 8-bit 24fps MP4 PLEX Test 22 – How well does it perform?
After giving the QNAP TS-251B a easier file, I ramped the difficulty right back up again with another H.264 media file that was at 40MB/s bitrate and at 1080p resolution – I wanted to see if the earlier results were a fluke and to see how the QNAP TS-251B handles this heavier file. There was a noticeably change in CPU use, but the results bore similar results to before.
Test File Type
- 1080p Resolution
- HEVC Codec
- 24FPS Frame Rate
- 40MB/s Bitrate
- 8 Bit Depth
- h.264 Compression
- MP4 File Container
- 24p Video Frame Rate
I hope these Plex Media Server 4K results were of use to you and this helps you consider which NAS you wish to you buy in 2018, whether it is the QNAP TS-251B or something more or less suited to your needs.
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