采样

参考

面板

渲染 ‣ 采样

积分器是一种用于计算光照的渲染算法。目前,Cycles引擎支持一种积分器,一种带直接光照采样的路径追踪积分器。它可以很好地适用于各种照明设定,但不适用于焦散以及其它一些复杂的光照情形。

光线从摄像机出发射到场景中,并来回反弹,直到它们找到一个光源,例如一个灯光物体,一个发光物体,或是环境背景光。为了找到灯光或发光的表面,间接照明采样(让光线跟随表面BSDF)与直接照明采样(选取一个光源并追踪射向它的光线)都将会用到。

Viewport Samples

在3D视图中使用的样本数。当设置样本数为零时,3D视图中将会不断采样。

Render Samples

这是最终渲染中单像素的光程追踪次数。采样次数越多,结果中的噪点就会越少,也会更加精确。

Time Limit

Renders scene until time limit or sample count is reached. When the time is set to 0, the sample count is used to determine when the render stops.

Note

The time limit does not include pre-render processing time, only render time.

自适应采样

启用 自适应采样 后,Cycles会自动减少噪点较少区域的采样,可以更快地渲染并且得到更均匀的噪点分布。例如角色的头发可能需要很多采样,但背景需要较少的采样。

通过自适应采样还可以渲染具有目标噪点量的图像。设置 噪波阈值 (通常范围为0.1到0.001),然后将渲染采样设置为较高的值,渲染器将自动选择合适的采样数。

噪波阈值

用于决定是否继续采样的阈值。典型值在0.1至0.001的范围内,较低的值表示较少的噪点。将其设置为0,则Cycles可以基于总采样数来猜测一个自动值。

最小采样

The minimum number of samples a pixel receives before adaptive sampling is applied. When set to 0 (default), it is automatically set to a value determined by the Noise Threshold.

降噪

降噪将移除在3D视窗的 渲染 模式下预览渲染时产生的噪点,或者移除在最终渲染时产生的噪点。

渲染

Denoising for the final render can be enabled or disabled with the checkbox. For denoising the image after rendering with the Denoising node, the Data Render Passes also adapt to the selected denoiser.

  • 开源图像降噪

    使用Intel的 开源图像降噪,一款基于CPU的AI降噪器。

    OptiX

    使用人工智能算法去除渲染中的噪点。它基于 OptiX — NVIDIA 加速引擎,因此具有与Optix渲染相同的GPU要求。

视窗

用于3D视图的 渲染 模式的降噪,可在设置中的复选框中启用或者禁用。

  • 自动

    为3D视图渲染使用最快且可用的降噪器(如果 OptiX 可用,则使用它,否则切换至 开源图像降噪)。

    开源图像降噪

    使用Intel的 开源图像降噪,一款基于CPU的AI降噪器。

    OptiX

    使用人工智能算法去除渲染中的噪点。它基于 OptiX — NVIDIA 加速引擎,因此具有与Optix渲染相同的GPU要求。

起始采样

开始3D视图 降噪 的采样。

输入通道

Controls which Render Pass the denoiser should use as input, which can have different effects on the denoised image. Generally, the more passes the denoiser has to denoise the better the result. It is recommended to at least use Albedo as None can blur out details, especially at lower sample counts.

  • Denoises the image using color data.

    反照率

    Denoises the image using color and albedo data.

    Albedo + Normal

    Denoises the image using color, albedo, and normal pass data.

Prefilter

Controls whether or not prefiltering is applied to Input Passes for use when denoising. Visible only when using OpenImageDenoise.

  • Does not apply any prefiltering to the input passes. This option retains the most detail and is the fastest, but assumes the input passes are noise free which may require a high sample count. If the input passes aren’t noise free, then noise will remain in the image after denoising.

    快速

    Assumes the input passes are not noise free, yet does not apply prefiltering to the input passes. This option is faster than Accurate but produces a blurrier result.

    Accurate

    Prefilters the input passes before denoising to reduce noise. This option usually produces more detailed results than Fast with increased processing time.

高级

随机种

不同的采样种的值积分器会给出不同的噪点模式。

  • Use Animated Seed (clock icon)

    为每一帧给出不同的种子值。制作动画时启用此功能是一个好主意,因为在现实世界中,每个帧都有不同的噪声模式。

图案

Random sampling pattern used by the integrator. When 自适应采样 is enabled, Progressive Multi-Jitter is always used instead of Sobol.

  • Sobol

    Uses a Sobol pattern to decide the random sampling pattern used by the integrator. See Sobol sequence on Wikipedia for more information.

    渐进式多重抖动

    Uses a progressive multi-jitter pattern to decide the random sampling pattern used by the integrator. Its advantage is to provide a good distribution of samples over iterating sample counts. Because of its good distribution over a range of different sample counts, this sample pattern is used for Adaptive Sampling. See this Pixar paper for more information.

Sample Offset

The number of samples to skip when starting render. This can be used to distribute a render across multiple computers then combine the images with bpy.ops.cycles.merge_images

Scrambling Distance Multiplier

Lower values Reduce randomization between pixels to improve GPU rendering performance, at the cost of possible rendering artifacts if set too low.

  • 自动

    Uses a formula to adapt the scrambling distance strength based on the sample count.

  • 视窗

    Uses the Scrambling Distance value for the viewport rendering. This will make the rendering faster but may cause flickering.

最小光线反弹

每个路径的光反弹数最小,之后积分器使用俄语轮盘终止对图像贡献较少的路径。设置较高的噪声会减少噪点,但也可能大大增加渲染时间。对于低反弹次数,强烈建议将其设置为等于最大反弹数。

最小透明反弹

透明反弹的最小数量。设置较高的设置可降低第一次反弹时的噪音,但对于头发和体积等更复杂的几何形状,效率也会降低。

光照阈值

当光贡献低于此阈值(噪声较多但渲染速度更快)时,可概率终止光样本。零禁用测试,从不忽略灯光。这很有用,因为在具有许多光源的大型场景中,有些场景可能只对最终图像贡献少量,并增加渲染时间。使用此设置可以减少计算光线所需的渲染时间,最终对图像的影响很小。

层采样

当渲染图层设置了每个样本图层数时,此选项指定如何使用它们。

  • 使用

    渲染图层样本将覆盖设置的场景样本。

    限界

    按场景样本绑定渲染图层样本。

    忽略

    忽略渲染图层采样设置。