AV1 capable Amlogic S905X4 processor has been expected for more than a year, and only now are we starting to see announcements of S905X4 TV boxes and development kits.
So it may be a good time to compare the features of the new Amlogic S905X4 processor again its predecessor, namely S905X3, and see if there are other notable differences apart from support for AV1 open video codec.
We’ll use data from S905X3 specifications, S905X2 vs S905X3 comparison, and a post on SDMC LinkedIn page.
Quad-core Cortex-A55 up to 1.91 GHz
Quad-core Cortex-A55 up to 2.0 GHz
Arm Mali-G31MP2 with support for OpenGL ES 3.2, Vulkan 1.0/1.1, and OpenCL 2.0
|Neural network accelerator|
Optional 1.2TOPS NPU
DDR3-2133, DDR3L-2133, DDR4-3200, LPDDR3-2133, LPDDR4-3200 SDRAM up to 4GB
eMMC 5.0, NAND Flash, SPI NOR/NAND, SD
HDMI 2.1 up to 4Kp60, HDCP2.2, CVBS
HDMI 2.1 up to 4Kp60, HDCP2.3, CVBS
HLG/HDR10/ 10+ Dolby vision, TCH PRIME
Stereo DACs, S/PDIF In and Out, 8-ch PDM, 12-ch PDM in, 12-ch PDM out
10-bit H.265, VP9, AVS2 up to 4Kp75, H.264 4Kp30
AV1 up to 4Kp120, 10-bit H.265, VP9, AVS2 up to 4Kp75, H.264 4Kp30
|Voice & Audio Processing|
VAD, ASRC/EQ/DRC, 2x HiFi4 audio DSP
|DRM & CAS|
Widevine, PlayReady, VMX, Irdeto MSR 3.2
Widevine, PlayReady, VMX, Irdeto MSR 3.2, Nagra NOCS3.2
Gigabit Ethernet MAC, and 10/100M PHY
|USB and PCIe||
1x USB 2.0, 1x USB3.0 or PCI-E v2+USB 2.0 (multiplexed)
AES, TDES, SHA-1/SHA-2/HMAC, SM4
AES, TDES, SHA-1/SHA-2/HMAC, RSA
2x Transport Stream (TS) inputs, ISO7816 smart card standard
Amlogic S905X4 will be slightly faster due to the higher (default) maximum CPU frequency of 2.0 GHz, but most people will not notice the difference. S905X4 is supposed to support Vulkan 1.1, while S905X3 does not, but I believe this is just due to more up-to-date Android SDK, and not differences in the silicon itself. S905X4 supports Nagra DRM, a more recent version of HDCP, and integrates a dual-core audio DSP which may be why there’s no optional AI accelerator. There are also some minor differences with the crypto engine.
So from a user perspective, the only real difference will be support for 4K AV1 hardware video decoding that boosts efficiency by 20% compared to H.265/HEVC, and saves 30% bandwidth compared to H.265/VP9. Since AV1 is supported by Netflix, Amazon Prime Video, YouTube, and other online video streaming services, you may experience less buffering for the same video quality, or higher video quality for an equivalent bitrate.
Jean-Luc started CNX Software in 2010 as a part-time endeavor, before quitting his job as a software engineering manager, and starting to write daily news, and reviews full time later in 2011.
The way the 10-bit has wrapped around on the S905X4 specs could lead people to think it has 10-bit h264 decode, whereas I think that refers to the newer codecs on the line above? (10-bit h.264 hardware decode is often requested but seldom provided – though I think some Rockchip processors do it)
Good point. I’ve updated the table to make it more clear. Yes, some Rockchip processors can handle 10-bit H.264 to some degree.
Eta prime has a YouTube video running a S905X4 American TV box. Amlogic has been doing a lot of worker with OTT makers and service suppliers.
Verizon Stream TV Review – The First S905X4 Android TV Box!
AV1 hands down. Where’s my Odroid-C5 with S905X4?
I want AV1 (and AV2) adoption as much anyone, but is it really true that AV1 saves 30% bandwidth compared to H.265? Looking at the Wikipedia article I see bitrate savings ranging from about 10-20% compared to H.265. That of course depends on a number of factors.
I’d like for this rollout to happen already so that most new devices come with AV1 decode, we get to see if unnamed patent troll lawsuits commence, and we can start talking about AV2 vs. H.266/VVC.
What’s RCA crypto? Was that an RSA typo?
Yes, sorry it’s RSA.
No worries, on the way to checking that, I learned what SM4 was, so that was a plus. 🙂 Thanks!
I don’t understand. How does essentially the same GPU on both products allow one to “handle” AV1 but not the other?
That’s because the GPU does not handle hardware video decoding. It’s a separate IP block called video processing unit (VPU).
That’s the case in most Arm SoC’s: https://www.cnx-software.com/2013/12/10/most-embedded-gpus-do-not-support-hardware-video-decoding-acceleration-the-vpu-does/
Due to lack of Amlogic support , no sdk or anything, there is no support from corelec and probably there will not be supported in future.
Is there a linux kernel for the s905x4 that would work with eg Armbian or another linux distro?