For years, H.264 has been the go-to video compression standard. Whenever you download a film or TV show, watch a Blu-ray, view HDTV broadcasts, or stream something from various sites and services, there’s a very good chance the video stream you’re watching has been encoded with H.264.
H.264 is a great compression standard for a number of reasons. It provides very good quality at relatively low bitrates, and its widespread use means it’s supported by essentially every video playback device made in the past five to ten years. It’s also very versatile, not only allowing compression to small file sizes, but also to high quality, high bitrate files that are suitable for use on Blu-ray discs.
While H.264 is doing a pretty good job of delivering compressed videos to users, there’s a better standard out there that offers similar quality at even smaller file sizes. The standard is called HEVC, or High Efficiency Video Codec, and it first appeared in 2013 as a true successor to H.264. For this reason, HEVC is also known as H.265, or MPEG-H Part 2.
HEVC’s main advantage over H.264 is that it offers roughly double the compression ratio for the same quality. This means that a video file encoded with HEVC can occupy half the space of its H.264 equivalent with no noticeable change in quality, or the same amount of space with improved quality. Sounds pretty good, right?
HEVC is able to compress files to a greater extent than before by evolving upon the H.264 standard. In both of these standards, motion compensated prediction is used to find areas that are redundant within a single frame or in the frames that follow. When redundant blocks of pixels are identified, they are encoded by referencing another area in the same or following frames. In H.264, these blocks can be up to 16x16 pixels in size, but big gains in compression were made by increasing this to 64x64 in HEVC.
Other improvements also help HEVC achieve greater levels of compression, including better variable-block-size segmentation, improved deblocking and motion compensation filters, sample adaptive offset filtering, and better motion vector prediction and precision. This page here from the x265 group has a great explanation of these terms and how it can improve HEVC’s efficiency.
As HEVC is relatively new to the scene, it’s not nearly as compatible with existing playback devices as H.264. Many such devices have dedicated hardware for decoding H.264 streams, while equivalent hardware for decoding HEVC is significantly less common. That’s not to say it’s impossible to decode HEVC on today’s devices – software playback is still possible on a wide variety of hardware, and some hardware decoding solutions exist – but something that can play H.264 is not necessarily HEVC-compatible.
Note: This feature was originally published on 02/16/2016. We have briefly revised it and bumped it because it's as relevant today as it was before (if not more, considering today's broader 4K support). Part of our #ThrowbackThursday initiative.
Here’s a quick rundown of well-known hardware that includes dedicated HEVC decoding blocks, which definitely support efficient HEVC playback:
- Intel 6th-generation ‘Skylake’ Core processors or newer
- AMD 6th-generation ‘Carizzo’ APUs or newer
- AMD ‘Fiji’ GPUs (Radeon R9 Fury/Fury X/Nano) or newer
- Nvidia GM206 GPUs (GeForce GTX 960/950) or newer
- Other Nvidia GeForce GTX 900 series GPUs have partial HEVC hardware decoding support
- Qualcomm Snapdragon 805/615/410/208 SoCs or newer. Support ranges from 720p decoding on low-end parts to 4K playback on high-end parts.
- Nvidia Tegra X1 SoCs or newer
- Samsung Exynos 5 Octa 5430 SoCs or newer
- Apple A8 SoCs or newer
- Some MediaTek SoCs from mid-2014 onwards
As you can see, most desktop hardware released in 2015, and most mobile hardware from late 2014 onwards, supports dedicated HEVC playback. Hardware designers have been more focused on getting HEVC decoding blocks into mobile hardware first, as the CPUs in these products typically aren’t fast enough for software decoding. Support in desktop hardware has been marginally slower as most desktop-class parts are powerful enough to decode HEVC without dedicated decoding blocks.
If you have a computer or device that doesn’t include the aforementioned hardware, that doesn’t mean you won’t be able to decode HEVC. PCs, even those with entry-level CPUs from several years ago, shouldn’t have much trouble software decoding HEVC videos. One of my HTPCs equipped with a $50 Intel Celeron ‘Ivy Bridge’ CPU from 2012 is more than capable of decoding HEVC, and I’ve even achieved smooth playback on Intel Bay Trail and Qualcomm Snapdragon 801 devices in some circumstances (albeit at high CPU utilization).
As a general rule of thumb, if you have an older PC you’d describe as “very slow” it probably won’t be capable of HEVC playback. Anything else will probably suffice.
Where you won’t find HEVC playback support is in many dedicated media players on the market today. These products either don’t support HEVC hardware decoding, have too low power SoCs to support smooth software playback, or only support a small handful of popular video formats without the ability to run wide format playback software like VLC.
Streaming Boxes and Console Support
Here’s a quick rundown of popular media playing devices that don’t support HEVC:
- Google’s Chromecast (first and second generations)
- Apple TV (although some reports suggest 1080p HEVC playback is possible by running VLC on a 4th-gen model)
- Roku (third-gen models and earlier)
- Amazon Fire TV (2014) and Fire TV Stick
- Any Western Digital WD TV products
- All PlayStation consoles (including PS4 Pro)
- Xbox 360
And here are the media players that do support HEVC:
- Roku 4
- Amazon Fire TV (2015) and 2nd-gen Fire TV Stick
- Xbox One
This isn’t an exhaustive list, but you can clearly see that there’s just a handful of very recent devices that support native HEVC playback. The Xbox One is the only console to support playback, although support for HEVC was added through a software update, presumably utilizing software decoding.
So while the benefits of HEVC encoding are clear, playback is essentially restricted to PCs, high-end smartphones and tablets, and a very small range of media players and consoles. At this point in time, compatibility is a disadvantage to encoding your media library in HEVC.
As for software that can playback HEVC-encoded files, there are many options out there. On Windows 10, you can natively play HEVC videos in the default Films & TV app or through Windows Media Player. Alternatively, you can use VLC or MPC-HC for playback, which support older operating systems, or popular media center apps like Kodi (version 14 onwards) and Plex Media Player.
If you’re running macOS or iOS, VLC is your best bet. On Android devices, you’ll be able to play back HEVC files using MX Player through software decoding if your device is fast enough, or if it is, both MX Player and the Plex app supports native HEVC playback. Note that some devices have HEVC decoding blocks in their SoCs but don’t support native playback at this time.
HEVC Versus H.264 Playback Performance
For devices that can decode HEVC video, performance is a concern. As HEVC compresses video streams to a greater extent than H.264, it requires more processing power to decompress; a pretty typical trade off when it comes to compression algorithms.
The difference in hardware utilization is particularly significant when comparing HEVC software playback to H.264 hardware-accelerated playback. This is a situation that will be common to most current-generation devices, as H.264 hardware decoding is very common, whereas we’re only starting to see HEVC hardware decoders on the market.
For mobile devices, HEVC’s greater hit on performance naturally leads to a greater hit on battery life. Again, this is a trade-off that users, at least for the next few years, will have to consider when encoding or playing HEVC content. The standard may allow you to view 4K streams while consuming less bandwidth, but your handset may run out of juice earlier than expected.
To see just how HEVC and H.264 differ from a performance perspective during playback, I ran some benchmarks on a collection of reasonably recent hardware.
Across the four PCs I tested both the HEVC and H.264 files on, typically there was only a small performance hit when playing back the HEVC files. On an Ivy Bridge Intel Core i5-3570 desktop, CPU utilization roughly doubled, but sat under 10 percent when playing back HEVC files. There was a wider gap in utilization on our Broadwell-based Dell XPS 13, although again utilization sat below 10 percent in both cases, with very impressive results while decoding H.264.
The Skylake Dell XPS 13 is the only device tested here that has support for hardware HEVC decoding. Unsurprisingly, this resulted in very low CPU utilization while decoding HEVC, and even though utilization was noticeably higher than decoding H.264, it was still low enough to not be of concern.
On a low-performance HTPC, built using an Intel ‘Ivy Bridge’ Celeron G1820, decoding HEVC wasn’t particularly troublesome either, despite CPU utilization sitting in the 45 to 65 percent range. Even though this may sound quite high, I never experienced any stuttering or decoding issues on this system.
I also recorded the median clock speeds that each processor sat at while decoding both H.264 and HEVC. In most circumstances, there was only a small 100-200 MHz jump in clock speed while decoding HEVC, which helps with power consumption. Across the board, as CPU utilization was below 100%, the CPU never ran at its full clock speed while decoding these files, which is a great result.
To start our battery life results, I’ve recorded figures from two smartphones that support hardware HEVC decoding: the Snapdragon 810-powered Sony Xperia Z5, and the Exynos 7420-powered Samsung Galaxy S6. While playing back the same Game of Thrones video on both handsets, encoded in either H.264 or HEVC, there was essentially no difference in battery life. This is a fantastic result, as it makes it much easier to justify encoding files in a space-saving HEVC format.
On a laptop without HEVC hardware decoding, the Dell XPS 13 with Broadwell inside, we saw a reduction in battery life of four hours. This is a pretty significant drop, and highlights the importance of having hardware decoding support in your battery powered devices. When moving up to a newer XPS 13 with Skylake inside, the inclusion of hardware decoding again reduces the battery life gap to zero.
How to Encode HEVC: The Set-Up and Test Files
Now that we’ve looked at how to playback HEVC-encoded files, it’s time to create them. There are a whole collection of tools and utilities that can encode HEVC, but in this article I’m going to focus on those that are easiest to use and provide the best quality options.
Throughout this section I’ll be looking at encoding two TV show episodes I ripped from a Blu-ray earlier. If you want to learn how to rip Blu-rays, there are plenty of guides around, and plenty of ways to do so. For this guide, however, I created two high-bitrate H.264 files that are of excellent quality, essentially representing what you’d get from the source material.
It should be noted here that if you rip a Blu-ray at original quality you will get a massive file size as Blu-rays use high-bitrate media for the ultimate in quality. Whether you use original quality or slightly compressed files really doesn’t matter, as encoding to lower bitrate H.264 or HEVC will lead to a slight reduction in quality for either type of file. The end result will usually be the same as well: a 10 GB Blu-ray source or a medium-bitrate 2.5 GB H.264 rip will both be compressed to 700 MB using the same HEVC settings, for example.
What I wouldn’t recommend doing is ripping your Blu-rays to a low quality file before re-encoding them to HEVC, as you can expect to lose even more quality in the process. In general, you want a source quality file before compression to deliver the best results, although most files you acquire through more dubious means should also suffice.
A single, high-detail frame from The Big Bang Theory sample used for encoding test purposes
The two files I’ll be using as examples in this guide are as follows:
- Game of Thrones, Season 2, Episode 1: 1920 x 1080, approximately 5,000 kbps H.264 with 1,500 kbps DTS 5.1 channel audio, encoded using x264
- The Big Bang Theory, Season 8, Episode 11: 1920 x 1080, approximately 9,000 Kbps H.264 with 1,500 kbps DTS 5.1 channel audio, encoded using x264
The Game of Thrones file is of higher visual quality due to the way the show was filmed and produced, with excellent detail, motion scenes, panning, and some dark environments. It’s a very good test bed for a typical TV show or movie file. The Big Bang Theory is of lesser visual quality despite its high bit rate, due to a differing camera setup. It also has less movement and detail, representing many sitcom TV shows that you may be wanting to encode.
This is a frame from the Game of Thrones test file
I also want to explain some terms before encoding these files:
- MP4 and MKV are containers, which are used to house the video and audio streams. In the case of MKV files, subtitles are also embedded in some circumstances.
- H.264 and HEVC are coding formats, and describe how to encode a video file using the accompanying compression standard
- x264 and x265 are encoding libraries, used to create H.264- and HEVC-encoded videos respectively
Therefore, it’s correct to say that we’ll be creating MKV files which include HEVC video streams encoded using x265.
For both H.264 and HEVC encoding using the CPU, we’ll be using Handbrake, and you’ll need at least version 0.10.0 for x265 support. I’ve used version 0.10.3.0 64-bit for this guide, which was the latest version at the time.
As a benchmark, I’ll be comparing encoded HEVC files to a compressed H.264 file created using what I believe are settings that achieve a great balance between small file size and quality. This includes using Handbrake’s constant quality setting at 23 RF for 1080p files, strict anamorphic picture size, and the following collection of advanced settings and filters. Note that to use the advanced settings, you’ll need to tick the appropriate box in the videos tab
For all audio files, whether it’s encoding H.264 or HEVC, I’ll be compressing to 5.1 channel HE-AAC with a bitrate of 256 kbps. If you’re more of an audiophile or if you’re encoding a movie, you might want to consider increasing the bitrate or using a different codec, but I find these settings to be perfectly fine for most TV shows.
How to Encode HEVC: Handbrake Settings to Use
While I’ll be exploring other encoding options later in this article, this page will give you step-by-step instructions on how to set Handbrake to encode small, high-quality HEVC files.
- Firstly, you’ll want to change the video codec under the Video tab from H.264 to H.265 (x265).
- Also, change the container from MP4 to MKV so that you can embed subtitles if you want to.
- Input the file you want to be transcoded by clicking the large Source button and then File (clicking Folder allows you to easily set up batch encodes). Then set a destination by browsing to whatever folder you desire.
- Head to the Picture tab, and set Anamorphic mode to strict. Also check to make sure the automatic cropping feature has detected the correct settings. Sometimes it will erroneously crop out a few pixels on any side, but you can address this by switching to custom with 0 set in every location box. If, however, you have a 21:9 video encoded in 16:9, the cropping feature will automatically crop out the black bars at the top and bottom.
- In the Filters tab, you’ll only want to modify these settings where necessary, leaving everything else ‘off’. If a TV show is interlaced, for example, it’s a good idea to set Decomb to Fast as this will only deinterlace frames that are visibly interlaced. If you want to remove noise or grain from a source, setting Denoise to hqdn3d with a custom preset of 1:1:4:4 is a solid choice.
- In the Video tab you’ll want to select some specific settings. Make sure framerate is set to ‘same as source’ and that the ‘Use advanced video tab instead’ box is unchecked.
- Then, select an x265 preset of Medium by adjusting the slider down from the default Ultrafast setting. On the next page I’ll explore how the x265 preset determines encode times, file sizes and quality, but basically you want to leave it on Medium for the best balance of encode time and file size. Setting it higher will result in a larger file and faster encodes, and setting lower will reduce the file size at the expense of significant longer encode times.
- As for quality, set this to Constant Quality with a value of 23 for 1080p videos, and slightly higher (22) for 720p videos. This is the slider you’ll want to experiment with the most: adjusting it closer to 0 gives better quality and higher bitrates, while moving it the other way has a negative effect on quality and delivers smaller files. I find 23 to be a great balance between quality and file size, although if you’re willing to put up with more compression artefacts, experimenting with 25 or lower is a good idea. However, I wouldn’t go any lower than 30 or any higher than 15 for the best results.
- As I mentioned earlier, in the Audio tab you’ll want to change the codec to HE-AAC (FDK), the bitrate to 256, and the mixdown to 5.1 channels. If your source has only 2.0 channel audio, leaving the setting on 5.1 will still encode only 2.0 audio; in other words, it won’t transform a stereo source into surround sound using any filters or magic. Here you might want to play with bitrates to whatever you desire, although I think 256 delivers great quality for TV show audio.
- Optional: Pass through any subtitles from your source by heading to the Subtitle tab, clicking Add Track, then selecting Add All Remaining Tracks. From here you can also “burn in” subtitles, which codes the text into the video stream so you can see the subtitles on video players that don’t support in-file subtitles (though you can’t turn off the subtitles). Setting subtitles to “forced only” tells a video player to display subtitles even when the audio track matches your set language: this is useful for displaying a subtitles when dialogue isn’t in English; for example, during alien conversations in a sci-fi film.
- Optional: Save these settings as a preset so you can revisit them easily in the future.
- Now you should be all good to go. Click Start and let the encode happen, which may take a considerable amount of time depending on your hardware. After the encode is done, text saying ‘finished’ will appear in the bottom left corner.
How to Encode HEVC: Utilizing Nvidia GPU Hardware Acceleration
If you happen to have a Maxwell-based Nvidia graphics card from the GeForce 900 series or later, you can utilize your GPU’s dedicated HEVC encoding block to transcode videos into HEVC significantly faster than by using Handbrake. While only some 900 series GPUs feature a HEVC decoding block, all include HEVC encoders, which is going to come in handy.
While performance is significantly improved by using Nvidia’s HEVC encoder, NVENC, it comes at a cost of quality. Simply put, you’re not going to get as good a quality at the same bitrates using Nvidia’s encoder compared to using Handbrake. You can check out a comparison on the pages that follow, but essentially the quality of Nvidia HEVC encodes is equivalent to a good H.264 encode, albeit with a much faster encode time.
Anyway, if you want to use NVENC to encode HEVC videos, you’ll need to download a program called StaxRip. The version I used for this guide was x64 220.127.116.11 beta.
- The interface for StaxRip is quite different to Handbrake. Firstly, you’ll want to drag your source file into the Source box, click Automatic when the pop-up appears, and then click okay. The program will then briefly demux the file to prepare for encoding.
- After that’s done, you’ll want to keep most of the settings at their default, making sure to set the target file to wherever you want the new file saved.
- One thing you will want to change is the encoder. Click on the x264 text and change this to Nvidia H.265.
- Then, click on Encoder Options under the Nvidia H.265 header, and change the mode to CQP. Leave the other values at their defaults.
- Optional: Instead of selection CQP as the mode, select VBR. Then go back to the main StaxRip screen and change the video bitrate to whatever you feel is appropriate. You’ll probably need a bitrate of at least 2,500 kbps to achieve good quality for a 1080p file, in which case leaving the setting on CQP is a better choice. However, if you want to experiment with bitrates rather than quality selections, VBR is the mode for you.
- After choosing CQP mode, or optionally VBR, return to the StaxRip main screen. From there, click on the “Edit” text next to the audio box that by default should say “AAC VBR 2.0 ~115 Kbps”. In this screen choose AC3 as a codec with 6 channels and a quality of 256 kbps. Also, uncheck the normalize box. Again, you can play around with these settings to adjust the audio delivered with your video.
- Click Next, then Start to begin the encode. Eventually it will complete itself and notify you in the log screen that appears.
HEVC Versus H.264 Encoding Performance
Let’s take a look at how the various encodes perform. Throughout the following section, all encodes were made using Handbrake with the settings as mentioned, with the exception of the Nvidia encodes, which were performed using StaxRip. My personal rig was used for testing, which is equipped with a modest Intel Core i5-3570 quad-core CPU at 3.4 GHz, 16 GB of DDR3 memory, and an Nvidia GeForce GTX 980 Ti.
The following presets were tested:
- H.264 Custom: Settings listed on Page 3, QF 23
- H.264 Handbrake Deafult: x264 Very Fast, Main Profile, Level 4.0, QF 23
- HEVC Medium: x265 Medium Preset, QF 23, default otherwise
- HEVC Faster: x265 Faster Preset, QF 23, default otherwise
- HEVC Medium: x265 Medium Preset, QF 23, default otherwise
- HEVC Medium QF 15: x265 Medium Preset, QF 15, default otherwise
- HEVC Slow: x265 Slow Preset, QF 23, default otherwise
- Nvidia HEVC: CQP mode at default settings
For our Game of Thrones test file, there is a lot that can be deduced from the above data. Firstly, the x265 Faster preset was significantly slower than the Ultrafast preset, while actually delivering less compression. Secondly, the x265 Slow preset was enormously slower than the Medium preset, while delivering a very similar file size. Of course this says nothing about quality, which we will explore later, but purely based on this data it’s very easy to remove the Faster and Slow presets from contention.
It's also plainly obvious that the Nvidia HEVC encoder is significantly faster than anything else due to its hardware encoding advantage. It creates a slightly larger HEVC-encoded file than Handbrake’s default H.264 settings in under half the time. Also, looking at the Efficiency Score (final file size * encoding time) metric, which essentially evaluates the compression efficiency in a lower-is-best fashion, it clearly blows away the competition.
If you’re after the smallest file possible, HEVC Medium beats my custom, excellent-quality H.264 settings in file size (it’s 56% smaller) with an encode that took 38% longer. It’s also more efficient than the HEVC Slow preset, but falls behind the Ultrafast preset, which delivers a 21% larger file in 63% less time.
The overall winner will still need to be determined by quality, but there are already some clear winners: Nvidia’s HEVC encoder is the most efficient, and the HEVC Medium preset does the best job of compression. For those without a current-gen Nvidia GPU, the HEVC Ultrafast preset is looking good. From these results it’s hard to see why you would bother encoding in H.264 unless you were more concerned about compatibility than compression.
It’s a similar story looking at encodes of The Big Bang Theory. Nvidia’s HEVC encoder created a decent file size in a very fast time of just four minutes, at a whopping 158.6 frames per second. Again, the Faster preset is slower and delivers less compression than the Ultrafast preset, while Medium is looking like a solid bet for the smallest file size.
Due to the amount of encodes I performed for this article, it’s hard to produce every single relevant side-by-side comparison for this section. Instead, I’ve included what I believe are the most relevant comparisons, and if you want to compare further, you can download this archive of lossless, full-resolution screenshots comparing each encode.
You'll need to look closely to spot the differences in the frames below. As we're looking at different forms of compression, the images generally look pretty similar, except in fine details. Typically you can spot the better encode by looking for sharper detail on faces and fabrics such as shirts; less blocking in blurred backgrounds or other smooth gradient areas; and fewer artefacts.
The frames that follow are 1100 x 600 crops of the full 1920 x 1080 frame. They are not downscaled in any way.
I’ll start by comparing the difference in quality between the default H.264 preset in Handbrake (x264 Very Fast) and my custom settings. My custom preset delivers significantly improved fine detail, less background blocking, and better clarity during moving scenes. However, this isn’t a surprise as it uses a higher bitrate to achieve this quality, producing slightly larger files.
It should be noted here that my custom H.264 preset comes the closest to the source material of all the encodes I performed for this article. The source does have higher quality throughout, though with a file size around three times larger.
Here you can see the difference between the two best presets in my opinion: x265 Medium and my custom H.264 preset. There is very little difference in visual quality, with a slight advantage to H.264 in very fine detail and background clarity. When playing back the video, the differences between the two are practically indistinguishable.
This is a great result for HEVC, as it exhibits nearly identical quality in a file less than half the size. Encoding times were increased by 45% on average to achieve this quality.
Interestingly, there is almost no visual difference between the Faster and Medium HEVC presets. If anything, Medium is slightly better quality when displaying facial detail, at a smaller bitrate.
And again, Medium isn’t any different to Slow when it comes to visual quality. For all intents and purposes, these two presets are identical in quality, and with a very similar file size and significantly slower encodes, the Slow preset isn’t worth using.
There is no point using Nvidia’s HEVC encoder for low bitrate encodes: the quality is horrible in comparison to an x265 Medium encode, with reduced detail across the entirety of the frame. Even though the dedicated Nvidia hardware encodes the file much faster, the quality is so poor from this identical-bitrate comparison that it’s not worth using.
There is a slight difference between Nvidia’s HEVC encoder set to CQP mode compared to the x265 Medium preset. Medium has a small advantage in fine still detail here, and slightly less blocking, at a significantly smaller file size. Nvidia has a slight advantage in detail during high motion scenes, although this isn’t surprising considering its superior bitrate.
Nvidia’s encoder has a small quality advantage over the x265 Ultrafast preset in most circumstances, however Ultrafast encodes end up being significantly smaller.
By extension, Ultrafast encodes are also inferior to Medium encodes, although they take less than half the time to encode.
And just in case you were wondering how the HEVC Medium encode compares to the original, these are the comparisons for you. Note that the HEVC Medium preset delivers a file just one fifth the size of the original Blu-ray rip (525 MB versus 2.5 GB).
Viewing these cropped and (slightly) compressed comparisons on a computer monitor isn’t the best way to directly compare the image quality. For the best comparisons, check out the archive that includes every scene I used above for every encode in high-quality images.
Wrap Up: HEVC Is Best
From all the testing I performed for this article, it’s clear that HEVC provides the best quality at the smallest file size, if you’re content with the downsides and restrictions that the format brings.
Of all the encodes I produced, here is the list from best to worst in terms of quality:
- H.264 Custom
- x265 HEVC Medium/x265 HEVC Slow
- x265 HEVC Faster
- Nvidia HEVC CQP
- x264 H.264 Very Fast
- x265 HEVC Ultrafast
- Nvidia HEVC VBR Low Bitrate
With Medium HEVC encodes occupying the least space of everything I encoded, it clearly takes the crown for the ultimate encoding profile that you should be using above all else. This includes H.264, because even though I achieved better quality from a custom H.264 preset, the files were more than twice as large.
If you’re less concerned about space and more concerned about efficiency, I would strongly recommend using Nvidia’s HEVC encoder on the default CQP settings. It produces files that are around twice as large as the Medium x265 preset, but it encodes these files significantly faster than anything else. Quality is much better than x265’s Ultrafast settings, and slightly better than the default x264/H.264 settings in Handbrake, albeit at higher bitrates than both.
If you don’t have a current-gen Nvidia GPU and you’re not keen on lengthy encodes, I’d recommend sticking to either HEVC’s Ultrafast preset or the default x264 Very High preset. Ultrafast HEVC is a bit more than twice as slow as x264 Very High, but it produces smaller files at only a small reduction in quality.
Of course, my recommendation to use the x265 Medium preset in Handbrake at constant quality of QF23 is only a suggestion, and you might find better results with your media by experimenting with the settings available to you. As I mentioned earlier, adjusting the constant quality slider is your best bet for increasing/decreasing the quality at the expense of bitrate, and adjustments may be needed for some files. It’s particularly worth experimenting if you are encoding animated TV shows, such as Family Guy.
There are still questions over whether encoding to HEVC at an intensive x265 preset like Medium is a better option than simply buying more hard drives to store larger files. 3 TB hard drives are currently just $85, while power costs are 12 cents per kWh in the United States on average. Depending on the performance of your rig, its power consumption, and the quality you want to achieve, it may be better to simply buy more hard drives.
Having a library of HEVC files may also not be suitable for your use cases. The format is new enough that it’s not compatible with a variety of popular media player hardware, although this will improve with each new hardware generation. It’s more hardware intensive to decode as well, which affects battery life on mobile devices, while older hardware may not be powerful enough to decode it at all.
And finally, if you’re an impatient person, the extra time it takes to encode to HEVC versus even a high-quality H.264 file may become frustrating.
But if you really want the best quality files in the smallest possible format, HEVC is the way to go. For this very reason, it’s no surprise to see the industry pushing for widespread HEVC adoption, or adoption of a similar low-bitrate, high-quality format. Moving away from H.264 to HEVC or an equivalent is especially important for 4K streaming, as the bandwidth requirements can be reduced significantly by simply encoding the media in a more compressed format. HEVC is perfect for this: it provides the same quality as H.264 streams at half the bitrate.
Even if 2016 isn’t the year where HEVC becomes widely adopted, testing out what the format is capable of has taught me at least one thing: the impending death of H.264 has been flagged, and it’s time to prepare for a new generation of better, more efficient encoding formats.