What is the difference between directsound and waveout?

Q What is the difference between directsound and waveout?
A waveout is an old and outdated 32-bit windows application for playing digital audio.
Application
Programming interface (API ). The old Windows operating system (such as Win9x winnt4) is in WAV
Eout has a high degree of completion (because waveout is designed for these operating systems), if you want the best
You should use waveout output on these operating systems. However, the function of waveout is limited.
It cannot support the "mixed multiple audio streams" function. This shows the waveout in win2kxp, just
The compatibility of the old software is provided, and therefore the waveout completion in win2kxp is very poor.
Which hardware acceleration function, all sound mixing operations are performed by software (so when the CPU usage is very high
Such as CD jumpers ).
Directsound is a newer and more modern sound playing API, which has been built into the latest 32-bit Windows operating system.
Operating System.
Directsound supports mixing multiple audio streams, independent volume control, hardware acceleration layer, and hardware simulation layer (if
Some functional hardware is not supported and can be simulated using software, so programmers don't have to worry about their new l33t
Code cannot run on the old voice card 16 ). In general, as long as your operating system is installed with the appropriate sound card driver
Programs and the latest DirectX and direstsound should all work well (except winnt4 ). In
In win2kxp, directsound is better than waveout, because in these operating systems
The degree of completion is higher than that of waveout (it consumes less CPU resources than waveout, and has a higher degree of freedom.
There is no common small fault with waveout ). Directsound was originally designed to allow the game to take advantage of system hardware
Acceleration function without directly accessing low-level hardware functions (just like other DirectX components ).
Q why is directsound always more vocal than waveout?
In win2kxp, changing the waveout volume seems to change the overall volume setting. However, directsou
The nd volume is independently controlled. In other words, you use waveout to play the music, you set the volume to 50%, you
Then you can get a 50% volume and use directsound to play the video. If you set the volume to 50%, you only get the most
25% of the total volume. Solution: Do not use waveout and set the volume to the maximum value in the Windows volume control.
.
Q is the quality of sound output between directsound and waveout different?
A1 in win2kxp (or using a WDM driver), waveout and directsound are only transmitted in P
There are two differences between cm and Windows Kernel mixer. Waveout only uses software sound mixing, so less
This causes special problems in the system, and dircetsound can use hardware sound mixing, which may cause some known,
Sound quality problems.
A2 in Win9x, The directsound driver system is completely isolated from waveout, and uses the low-level method
Control the hardware, so it is like using two different drivers to work with waveout and directsound. In use
When sound cards of some old ISA interfaces are used, directsound has audio
Data reduces the sampling rate to 22 kHz 8 bit (or other similar sampling rate.
Q What is the difference between software mixing and hardware mixing for directsound?
A In WINXP SP1 and DirectX 8.1, whether it is using Microsoft's directsound core or driver
Program for hardware mixing, it is easy to encounter problems. It has been confirmed that hardware mixing is used in WINXP.
When transmitting audio data, even if different sound cards are used, the sampling frequency problem may occur. In particular, some
Driver problems that have existed for a long time (the famous New Future audigy sound card skipping problem, in some settings
There will be intermittent, static noises in some cases, or even sudden drops in sound quality, Tian xiao
Why !). If you want to operate the computer stably, we recommend that you disable hardware acceleration. Hard
The driectsound field in foobar2000's preference can be found in & quot; allow hardw.
Are acceleration & quot ;. Enabling it does not mean that you have actually activated this function (directsound will be unavailable
Software mixing is automatically used when resources are used ).
Resampling)
Q if I use the re-sampling function, can I improve the quality of the sound?
A No. You cannot use the ressample to "improve" The quality of the sound. The re-sampling is a consumable process. You
You can change the size of a BMP image. The size of the modified image is very similar to that of the original one,
If you zoom in the two images, you will find that they are different in details. On some hardware
If you use high-quality re-sampling software, to avoid re-sampling the process with your driver hardware Processing
, You can avoid the loss of a large amount of data (that is, to avoid the reduction of audio quality ). I know the voice of some people
On card 16, the sampling rate was increased to 96 kHz, 24bit, and claimed to be able to hear a brighter voice (Fact
Windows Kernel mixer will reduce the sampling rate back to 44 kHz 16 bit), don't listen to what they said.
Q How many sampling parameters should I set?
A first, you should query the hardware information of your sound card. Some sound cards (for example, available before the awesome Series)
Noisy card) You do not need to re-sample, which means you don't need to re-sample to get the best quality (
There will be no quality reduction caused by re-sampling ). All live & #33; Series audigy series ac97 compatible sound cards
The sampling frequency of the output has been fixed to 48 khz. The quality of the re-sampling will be caused by the hardware device of the driver.
Windows Audio mixing settings change. In many cases, the SSRC re-sampling software takes precedence over your hardware driver
So you need to set the sampling parameters to 48khz16bits to avoid your hardware driver
Rows.
Q, But I can re-sample my audio card as 96khz24bits...
A. Of course, Windows musters will downgrade the sampling rate back to the format that your hardware can accept (for example, 48khz1
6 bits), which causes extra quality degradation. Do not increase the sampling rate unless your hardware can accept this
Format.
Dithering
Dither is called "delivery" in computer graphics, and it also has similar meanings in processing audio. There are three
As shown in the figure, you can see where the difference between dither is.
In the original graph (24-bit high color), the small square in the upper left corner is enlarged from the black box.
There is a dither image (8 bit 256 color), which is far away from the source image.
Without dither (8 bit 256 color), the color distribution is not smooth, and the fundamental difference with the source image can be seen. (Figure
Omitted)
If this function is enabled, dithering will be performed during waveform playback. If dithering is not activated, foobar20
00 will switch to split. This means that unused bits will be dropped and discarded. Fade in many quieter music
Or fade out, it will cause the "broken" Auditory effect (that is, the effect of fade in is not smooth ).
Dithering is true only when you play high (for example, 32bit) audio at low (for example, 16bit ).
Is in use.
Output bit depth)
Here is a drop-down menu that allows you to select the bit rate of the output. If you have a 24-bit sound card, of course you will
We want to use dither to 24bit to output unused bits. Even a 16-bit sound card is playing
The 32-bit dither to 16 bit audio can also improve sound quality.
Foobar2000 processes the following audio materials:
Decoder (32 bit FP) = & gt; [replaygain] = & gt; [DSP] = & gt; downsample to 1624 bit with option
Al dithering
Therefore, when you select dither to 1624bit, we recommend that you activate dithering. However, if it is set to 32bit
Do not need to activate dithering, because the data directly transmitted from the decoder is 32bit.
About kernel streaming
Q What is kernel streaming?
A kernel streaming will bypass Windows Kernel mixer and directly output the audio to the sound card. This
Mode has a low output latency, which may be considered as another option other than ASIO output.
Q should I use kernel streaming?
A. If your sound card and driver support and you use kernel streaming, there is no problem.
Next, we recommend that you use kernel streaming.
Q why is the Output Using Kernel streaming larger or brighter sound than the directsound output?
A's voice is not bright, but loud. Because the method for outputting data to the sound card is different
Windows Mixer
The volume control (wave) is invalid for Kernel streaming and is output at the maximum volume. If
You set the wave volume in the volume control to the maximum, and use directsound output, you will find that the sound quality and
The output of kernel streaming is no different.
Q which operating systems can use kernel streaming?
A kernel streaming only works on Windows 2000 and Windows XP. Some people say it should work.
Run on Windows ME.
How to Set
When foobar2000 is enabled, you will find that it does not even have play or stop buttons. You can go to fo
In obar2000 & gt; preferences & gt; display, select Show buttons and go to DSP manager.
To the left, and then in the resampler under DSP manager
E rate is set to your Soundcard sample
Below are some recommended values for rate (refer to the dearhoney RQP database)
44100-16, awe32, awe64 and other similar ISA Soundcard
48000-PCI, live, audigy1, audigy2, extigy, Philips AE, sonic fury, ya
Maha 7x4 and general onboard Soundcard
96000-audigy2 and some soundcards that really support 96 kHz, such as terratec's
After using resampler, try playing the two test signals mentioned above to see if they are pure
Sharp ultra-high frequency sound, and cannot hear the difference between two archives. If so, the high-quality SRC has been successful.
. Otherwise, go to foobar2000 & gt; preferences & gt; output and try to select different output, such as kerne.
L streaming (WDM driver only), change various settings in directsoundwaveout, and try again
If it still fails, try the Option & gt; advanced control in the Windows volume control to see if there is a high or low
Sound control. If yes, move the high and low sounds to the center and try again (if it is already in the middle, no need to move
If it still doesn't work, I have nothing to say. Note that Windows Audio is used when kernel streaming is used.
The wave output in the volume control may be uncontrollable, which is a normal phenomenon.
In the playback column, there will be an output bit depth option, which is only supported by Soundcard
24-bit (audigy1 is 16-bit, and audigy2 is 24-bit), because
If a 24-bit Soundcard is supported, selecting 24-bit will only make the sound quality worse than 16-bit, even if you may listen
No.
This is basically the case. Let's explore other functions.