A greater concern I'd say, is the complexity. Opus is relatively complex computational wise, which would use quite a bit of battery power.
Quote from: polemon on 26 August, 2017, 02:24:30 PMA greater concern I'd say, is the complexity. Opus is relatively complex computational wise, which would use quite a bit of battery power. Recently I have tested decoders of some popular lossy and lossless on pretty old Motorola E2 smartphone (Cortex A53, quad core 1.2 GHz, 28 nm).The fastest was LC-AAC 192x and slowest was Opus 52x. And all other decoders were inbetween these values.An interesting part that battery life were the same for ALL decoders (50+ hours). Some expalantion https://hydrogenaud.io/index.php/topic,113981.msg939076.html#msg939076Even Wavpack "Extra High lossless compression" which is 2x more CPU intensive than Opus had just slightly less battery life (~ 5-10% ) on this not so efficient 28 nm chip. And even these difference disappears on a newer ARM chips (20, 14, 10nm). >2x-4x complexity of Opus would be just as efficient as any other codec on these chips.As of encoders, all formats are pretty fast as well. Opus 1.2.x is very fast actually.
bstrobl referred to hardware decoders, which in my book includes ip-cores. Unless you find an ip-core or silicon hardware on a µC capable of decoding Opus, you're running into problems. The problem being mainly fast RAM, not the CPU itself. Fast RAM ("fast" in a µC sense) actually consumes the most power in these applications. When it comes to RF power, on one hand you're right, but this can be alleviated with Bt 4.0-LE probably to a certain extent. The other is, that Bt accessories like speakers and headphones mainly receive RF from a rather strong source (the phone is rather strong in comparison). Similar to like a UMTS/LTE phone is a rather low-power radio compared to a cellular tower transmitter.
[Actually, most of what people call "hardware" audio decoders are in fact just low-power DSPs running software. Custom silicon is still useful for video decoding, but audio is so cheap to decode that it doesn't actually matter. Now, when you consider the power required by the radio (RF), the (de)modulation (SDR) and the audio amplifier (for headphones), then the cost of decoding isn't a big deal.
If I am not mistaken, an AAC encode/decode license still costs 2$. That can be a pretty large part of the cost on a single headphone. The driving pressure to lower costs(people want cheap) may push future adoption of Opus as a bluetooth codec.
MP3 and other codecs have a high delay, making the experience sub-par for things like games, audio production etc.Opus does not have this issue and can deal better with lower bitrates. I sometimes am in a high RF noise area and SBC just collapses horribly making it useless.
Technically there doesn't seem to be any problem in adding in Opus to new devices once a manufacturer decides to do so. They might look at their use case (Voip or whatever) and decide adding Opus support is the way to go.
If there were no pressure at all to do anything we would all be using SBC and nothing else. Clearly there are other codec implementations, even if those take time to implement.
Companies do tend to sometimes look into the future and if an early implementation of something allows them to drop old stuff eventually they might do it if there is sufficient benefit (usually monetary).
Why support AAC, AptX, AptX low latency etc. when Opus can do the job of all of them?
Anyway LDAC is lossless for CD format 44.1/16.