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2024-03-07 20:33:12
Pika 1.0全面开放：使用教程及技巧，限时免费 - 知乎
Pika 1.0全面开放：使用教程及技巧，限时免费 - 知乎切换模式写文章登录/注册Pika 1.0全面开放：使用教程及技巧，限时免费Cedric聊AI致力于分享最新的人工智能技术、应用和趋势Pika于12月26日宣布了Pika 1.0全面开放的喜讯。我也在前几天幸运地获得了Pika 1.0的体验资格，现在就结合我的使用经验和网友们的分享，来为大家介绍Pika 1.0的使用教程和技巧。进入Pika官网（https://pika.art/），由于最近是圣诞假期，你会发现页面上布满了圣诞节的氛围。要创作新视频，只需在页面下方的对话框中输入提示词，然后点击星号按钮，你的AI视频就开始生成了。小贴士：在编写Prompt时，尽量使用简短的句子。与Midjourney的早期版本类似，避免使用太过“自然”的语言和长句。目前的视频生成技术，像早期的文生图技术一样，还不能处理太过细节的内容。也可以选择点击“Image or video”上传图片或视频，作为生成的基础。小贴士：使用一张高清晰度的垫图配合简洁的提示词，通常能取得较好的效果。此外，在提示框右下方有几个按钮，它们是参数选项，可以帮助用户更精细地控制视频生成的细节。第一个按钮允许用户调整视频的画面比例和帧数，最高可生成24帧的视频。小贴士：如果需要延长视频，可以将帧数设置为12，以防止最后一帧过于模糊，影响接下来4秒视频的清晰度。第二个按钮主要用于控制镜头运动和画面的运动强度。上方的选项可以控制镜头的上下、左右移动、旋转和缩放，下方的滑条则用于调节镜头速度。这个按钮的功能可以精确地控制整个视频的画面运动效果。第三个按钮允许输入负面词，以便更准确地控制提示词，还可以输入已生成视频的种子编号来生成类似的视频，同时还可以调节画面与提示词的一致性。小贴士：和Stable Diffusion一样，负面词效果明显。可以输入“Blur, out of focus, distortion, deformation, exposure”等词语来避免视频出现模糊、失焦、扭曲和过曝的问题。如果你看到了一个不错的视频，可以尝试输入相同的提示词、负面提示词、参数和种子编号，以生成类似的视频。对于画面与提示词一致性的参数，设置在5-10之间的效果通常最佳，避免画面出现变形或扭曲。视频生成完毕后，你可以在“My Library”标签页播放。当然，“Explore”标签页里也能观赏其他用户创作的视频。视频下方配备了众多实用的按钮功能，比如最下方的按钮，用于复制视频的完整提示词。位于最左侧的“Retry”按钮，能让你以相同的提示词和参数再次生成视频，但会采用不同的随机种子。新生成的视频会直接显示在原视频下方供你选择，或者你也可以点击左右方向键进行切换。点击“Reprompt”按钮，Pika会自动将该视频的提示词复制到下方的输入框中，方便你根据自己的想法进行调整，生成全新的内容。“Edit”按钮则是功能最为强大的工具，点击后，它会将选中的视频作为新视频生成的基础，同时衍生出两个新功能：“Modify region”和“Expand canvas”即“修改区域”和“扩充画面”功能。选择“Modify region”后，用户可以指定视频的特定区域，让Pika生成新内容。这个功能与Midjourney相似，但Pika针对的是视频。小贴士：区域修改时，确保白色边框涵盖物体在整个视频中的所有运动区域。选择“扩充画面”后，你可以缩小原视频、调整视频位置或画幅，再次生成时，Pika会填满整个画面。右侧三个点中隐藏了另外两项功能：“延长4秒”和“提升画质”。由于默认的视频生成长度仅为3秒，如果你对某段视频特别满意但觉得时间太短，可以使用“Add 4s”功能将视频延长至7秒。此外，“Upscale”按钮则可将高清视频提升至2K画质。小贴士：在延长视频时逐步降低相关性参数值，有助于最大程度提升一致性和稳定性。还可以在延长过程中调整运镜，实现更立体的摄影效果。最后，右侧还有两个按钮，左侧的分享按钮可以将视频分享到X或Facebook，或者你可以点击“Copy”按钮复制链接进行分享。最右侧的按钮则显示视频信息，点击后可以查看视频的画幅比例、帧率、运动速率、一致性和种子编号等信息。以上就是Pika 1.0的使用教程和技巧。目前，Pika的所有功能都是免费的，但不排除未来可能会开始收费，所以有兴趣的朋友不妨尽早体验。如果这篇文章对你有所帮助，欢迎点赞、收藏及分享。同时，请关注我，获取更多关于人工智能的最新资讯和见解！参考：https://twitter.com/pika_labs/status/1739345676486561977https://mp.weixin.qq.com/s/J8raD9KkcIjf3LE1VF-yxg编辑于 2023-12-27 08:06・IP 属地上海pikaAI视频人工智能前沿赞同 7添加评论分享喜欢收藏申请
目前最强文生视频AI工具PIKA上手指南 - 知乎
目前最强文生视频AI工具PIKA上手指南 - 知乎首发于在我忘记之前切换模式写文章登录/注册目前最强文生视频AI工具PIKA上手指南GlenPIKA是一个最近新出的超有趣的文字生成视频AI工具，除了可以直接生成视频之外，它还可以通过上传已有图片，然后添加提示字，让图片生成自定义视频。这就是文生视频2.0版了! 申请内测PIKA的官网是：https://www.pika.art点击进入，即可看到主页，然后点击“加入测试版”，即可申请内测，一般很快就能获得内测资格。简单介绍一下PIKA的特点： 生成视频的速度很快，只需要1分钟即可 目前是完全免费的! 它的生成平台是一个Discord服务器（需要魔法，先注册一下Discord）快速上手 PIKA生成视频的工作流程：先用MJ/SD生成图像（可选） + 在PIKA平台添加提示 = 得到视频要生成视频，需要进入generate频道，目前有10个generate频道，大家随便选择一个进入即可。在频道内，使用/create命令并输入你想要使用的提示，在频道中发送后，等待片刻即可。下面我来分享几个PIKA的视频生成案例，大家可以参考参考~案例1：只输入提示词（Prompt: beautiful moon），意思是漂亮的月亮。输出视频：https://www.zhihu.com/video/1673773005468610560案例2：输入用SD生成的图片+提示词（Prompt: A girl in the magical world, gazing at you, enchanting magic），意思是魔法少女，凝视着你。输出视频：https://www.zhihu.com/video/1673773031146070016不得不说，效果有点儿好！PIKA是一个非常有创意且易用的文字生成视频工具，大家快去试试吧！建议可以先用MJ或SD生成图，再上传到PIKA加提示，就可以轻松获取动态视频了！ 期待PIKA后续的迭代和新功能！发布于 2023-08-12 19:10・IP 属地广东工具人工智能工具软件赞同 78 条评论分享喜欢收藏申请转载文章被以下专栏收录在我忘记之前忘记之前留
AI 生成视频工具 Pika 1.0 的实际体验效果如何？ - 知乎
AI 生成视频工具 Pika 1.0 的实际体验效果如何？ - 知乎首页知乎知学堂发现等你来答切换模式登录/注册人工智能视频科技AIGC多模态大模型AI 生成视频工具 Pika 1.0 的实际体验效果如何？蹲一波内测显示全部 关注者102被浏览111,167关注问题写回答邀请回答好问题添加评论分享35 个回答默认排序数字生命卡兹克 关注PIKA1.0全网爆火后。我作为PIKA的超级合作者，一直盼星星盼月亮，等他们的PIKA1.0。等啊等，等啊等。在内部渠道登记了我的邮箱后。又过了一天。终于。收到了来自PIKA的邮件。瞬间激动的无以复加。我应该算是国内最先拿到PIKA1.0资格的几个人了吧。所以，PIKA1.0，我来了！！！当然，没排队的，可以先去https://pika.art/排队。说不定啥时候你也拿到资格了呢，笑。一进入PIKA，你就能看到一个非常空旷的界面。上面那些都不重要，核心是下面的操作区。PIKA1.0支持3种方式生成视频：文生视频、图生视频、视频转视频。右下角是3个新的设置，以前在Disocrd里都要手输入，体验太差，现在全部都拎出来了，点吧点吧就能设置。体验极好。第一个设置项可以选择比例（上传图片时比例设置禁用）和帧率。第二个就是镜头控制和速度。第三个是新增的负面提示以及提示词相关性。预告片里很炫的视频扩展（Expand canvas）和Modify region（区域修改），在生成视频后的二次编辑里就有，还有一个额外的放大增强和增加4s。界面大概浏览完了，一个一个来说。一. PIKA1.0新模型能明显感受到，PIKA1.0是启用了一个全新的模型，甚至我感觉不是基于旧有的迭代，而是完全重新做的一个全新的模型。强非常非常多。3D和2D的动画效果更是吊炸天。所以他们的新模型，我会多花一些篇幅和笔墨，来展现一下。首先，文生视频的质量得到了大幅度的提升。我直接写了一段：Prompt：Cinematic, happy laughing girl in office, Pixar style瞬间，匹配皮克斯水平的镜头就出来了。要知道，我只花了1分钟。这效果，我说实话，太特么吓人了。。。。。。而且，这稳定性，这神情。。。爆杀市面上所有的AI视频。再来！A cat flying a plane,Cartoon style在文生图这块，PIKA1.0的新模型稳定的令人害怕。Cinematic, extreme close-up of cars on the road in a jungle, 3D rendering不规则构图的汽车行驶在道路上，这个前进的镜头依然稳定的可怕，车上的光影更是表现的极好。无敌。真的无敌。同时，有两个小技巧是，右下角第三个设置里，负面提示（Negative prompt）可以常驻：blurry, out of focus, twisted, deformed。提示词相关性别设太高，可以5～15之间，自己实测下来效果最好。再来说图生视频。图生视频这块，效果也依旧棒。放几个case。（这里因为GIF图比较大所以只能放了每秒10帧的GIF，所以看起来可能有一些卡，这并不是PIKA的原因。）说实话，Runway原本剩的唯一优势就画质好+一致性强点了。。。但是你看看现在的PIKA1.0。。。。。。人的一致性已经逆天了，再加上它强到爆的语义理解，以及幅度巨大的动作。。。。咋比啊。。。这PIKA1.0新模型的质量，特别是它最擅长的3D和3D的动画的质量，真的让人激动到无以复加。二. 视频扩展因为手边没啥现成的视频素材，于是我先用PIKA1.0随手生成了皮克斯风格的女孩。再点这个Edit编辑。然后使用视频扩展功能，来给她女孩扩充一下。PIKA1.0的扩充，是只能扩充到它自己限定的那几个尺寸，不过也都是非常主流且常见的尺寸。原视频是可以在这个框中随意拖动的，比如我就想让这个女孩补充一下下半身（笑。我就把原视频拖到了最顶部，下面空出来了。然后，我们来看看，PIKA的扩充效果。还有啥可说的。。。。这一致性，这细节。。。。。我们再离谱点，再在这个基础上，做一个超大幅度的横向扩充。。。。还有啥好说的呢。PIKA，牛逼！PIKA，你就是传奇！三. 区域修改压抑着激动的心情，我开始测试区域修改。为了效果，我只能贡献出我自己的视频了。。于是，我在公司现场录了一个。。。这人长这样，大家将就下，别嫌丑，实在没素材了。。。。先给眼镜换个墨镜。上传视频后，就点开区域修改功能，在你要修改的地方，拉个框，然后写上prompt：墨镜。就。。。成了。。。。再给我自己换个猫头？好的，现在面对你的是猫兹克了。或者。。我变个性？说来就来！泪目了，受制于时间和篇幅，我没法大幅度的开发出PIKA的潜力，但是我相信，所有人都能看出来，PIKA1.0有多强。上面列出的3个大点，我相信是大家最关心的。当然，还有很多很多其他的功能，比如延长4s和一键增强。Add 4s：PIKA默认出来的是4s，你可以用这个功能继续延长4s。AI视频标配。Upscale：增强，直接原地放大两倍。类似MJ的无损放大，效果很好。还有类似Gen1的视频转视频，这个我觉得效果就一般般了。当然，还有我最喜欢的体验极佳的一键重试。点一下就能直接在同窗口生成多个视频，你可以开心的roll起来，而不用当心你的屏幕被roll的垃圾堆满。这体验不比狗屎Runway好太多了！！！四. 最后总结受制于时间和PIKA海量更新的关系，我这一篇文章，肯定没有办法做到全面的评测。但是先给大家解渴，以及破了PIKA1.0是来骗钱的谣言，我觉得是没有问题。PIKA1.0，就是我现在用过的所有AI视频工具里面。最牛逼的，体验最好的，效果最好的AI。没有之一！！！我相信随着越来越多的体验者，拿到PIKA1.0资格之后，真正用起来后，会有更多的玩法和黑科技出来。我期待着那一天。PIKA1.0，在我心中。你就是传奇。发布于 2023-12-07 11:44赞同 22917 条评论分享收藏喜欢收起李博杰人工智能话题下的优秀答主 关注这是最近一小时内用户在 Pika 的 Discord 频道里面生成的视频。每个生成的视频都是 3 秒，一共截取了 50 个，没有经过特别挑选，只是删除了一些画面基本上不动的视频。 Pika 用户生成的 50 个视频https://www.zhihu.com/video/1716096944370499584效果跟 prompt 关系很大，prompt 写得越详细，一般生成效果越好。大多数 prompt 写得一般，所以大多数生成的视频效果一般。Pika 频道里大量涌入的生成请求Pika 频道里已经生成的视频Pika 频道里已经生成的视频发布于 2023-12-07 14:15赞同 245 条评论分享收藏喜欢
Pika Labs 新魔法：一键将图像转为视频！ - 知乎
Pika Labs 新魔法：一键将图像转为视频！ - 知乎切换模式写文章登录/注册Pika Labs 新魔法：一键将图像转为视频！AI 数字人元峰大家好，我是元峰。作为 AI 超级个体的践行者，比较热爱研究和学习各种 AI 工具。最近随着 AI 视频技术的迭代，越来越多优质的 AI 大片进入我们的视线。5月份，我曾经分享过使用 LeiaPix Converter 将图片产生动态效果。前几天也分享过通过 Gen-2 将图片转化为视频。然而 Gen-2 的免费时长只有 90 秒，可能对于大量制作视频的你来说并不足够，但不要担心！现在，Pika Labs 推出了创新的文本和图像转视频平台，只需打字即可激发你的创造力。这个平台让你能够将旅程中的图像转换为 Discord 上引人入胜的视频！测试阶段是免费的！今天的内容，我会介绍如何使用 Pika Labs 将图像转为视频，希望你能充分利用这个工具，释放你的创作潜力，见证你的图像转变成精彩的视频。一、Pika Labs 介绍Pika Labs 是一款创新的视频创建工具，可以将文本和图像转换为引人入胜的视频。而且，我们可以在 Discord 中完成所有操作！今天，我们完成使用 Pika Labs 进行视频创作的迷人过程，通过输入我们想要的文本，我们的想法就会变得生动起来！二、视频生成——它是如何工作的？点击链接 https://discord.com/invite/pika 加入 Pika2. 一旦我们进入 Pika Labs Discord 服务器，请前往他们的“#generate”频道之一。3. 使用“/create”命令添加图像以及提示说明。4. 点击“回车”，视频就会生成。就是这么简单！与 Gen-2 不同的是，文本将提供对视频创建的更大控制，PikaLabs 可以更好地结合文本以与图像完美配合。钢铁侠正在飞继续测试提示正如你从上面看到的，由于钢铁侠看起来是没有动的，所以看起来有点奇怪，所以我将提示改为“钢铁侠正在飞往宇宙”，以更多的运动让它变得栩栩如生。这是结果！钢铁侠正在飞往宇宙这里还有更多视频。风中的狐狸风中的女孩三、创意用法除了简单地将图像转换为视频，还有一些创造性的用法可以提升我们图像的效果。一）令人垂涎欲滴的视频Pika Labs 非常适合在食物摄影中添加动感。它能够唤起情感、增添活力、突出质感，并在图像中营造一个故事。运动能够刺激食欲，使食物更具吸引力，展示其丰富度，并吸引观众。尝试在提示中加入以下运动关键词：Powder and Spices Exploding 粉末和香料爆炸Pulling of cheese 拉丝奶酪Sauce dripping 酱汁滴落Smoke and Flame 烟雾与火焰Water Splashing 水花四溅草莓掉落，水花四溅巧克力酱滴下来烟雾和火焰二）令人惊叹的风景它还非常适合结合动态效果来增强我们的风景和景观。尝试一下：Aurora 极光Lava Flowing 熔岩流动Shooting Stars 流星划过天际River flowing 河水流淌Tree moving 树木摇曳Waterfalls flowing 瀑布倾泻瀑布流淌在城市中移动的汽车和人添加天气元素是提升气氛的另一个小技巧：Raining 下雨Thunder and lighting 电闪雷鸣Foggy 有雾Sun shining in 阳光照进来雨中、雾里三）演示背景通过流动或滴落的动作增强令人惊叹的背景，非常适合互动展览和演示！Paint Dripping 油漆滴落Ink Spreading 墨水扩散Liquid Flowing 液体流动Watercolor Splashing 水彩溅射液体流动液体流动和飞溅四）让奇怪的图像变得更奇怪对于奇怪的图像，其效果也非常有效！张开嘴尖叫蜘蛛放屁，人们到处乱跑四、参数我们还可以通过文本提示和参数来简单创建视频，以下是目前支持的一些参数：-gs xx：引导比例，较高的值使其与文本更相关（推荐范围为8-24）-neg “xxx”：负面提示（指定在视频中不希望出现的内容）-ar xx:xx ：宽高比（例如16:9、9:16、1:1、4:5）-seed xxx：生成过程中增加一致性的种子数-motion xx：所需运动强度（仅支持0/1/2） 请注意，Pika Labs 的参数只需要一个破折号“-”。五、最后的想法我们在本文中深入探讨了如何使用 Pika Labs 平台将图像转化为动态视频。这一过程虽然充满乐趣，但也需要精确和细致的操作。正如你们所见，有时候，我们需要更精确地使用文本提示。添加太多操作可能会导致一些糟糕的视频。这就是为什么尝试和实验是如此重要的原因。每个项目都可能需要不同的方法和技巧，而找到最适合的提示可能需要时间和耐心。上面提到的所有关键字也可用于将我们的提示融入到 Midjourney 中制作图像中。发布于 2023-08-13 10:45・IP 属地甘肃pikaAI电影赞同 327 条评论分享喜欢收藏申请
GitHub - pika/pika: Pure Python RabbitMQ/AMQP 0-9-1 client library
GitHub - pika/pika: Pure Python RabbitMQ/AMQP 0-9-1 client library
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mainBranchesTagsGo to fileCodeFolders and filesNameNameLast commit messageLast commit dateLatest commit History2,498 Commits.github.github .vscode.vscode docsdocs examplesexamples pikapika testdatatestdata teststests utilsutils .checkignore.checkignore .codeclimate.yml.codeclimate.yml .coveragerc.coveragerc .gitignore.gitignore .readthedocs.yaml.readthedocs.yaml CHANGELOG.mdCHANGELOG.md CONTRIBUTING.mdCONTRIBUTING.md HISTORY.mdHISTORY.md LICENSELICENSE MANIFEST.inMANIFEST.in README.rstREADME.rst RELEASE.mdRELEASE.md nose2.cfgnose2.cfg pylintrcpylintrc pyproject.tomlpyproject.toml test-requirements.txttest-requirements.txt View all filesRepository files navigationREADMEBSD-3-Clause licensePika
Pika is a RabbitMQ (AMQP 0-9-1) client library for Python.
Introduction
Pika is a pure-Python implementation of the AMQP 0-9-1 protocol including
RabbitMQ's extensions.
Supports Python 3.7+ (1.1.0 was the last version to support 2.7)
Since threads aren't appropriate to every situation, it doesn't require
threads. Pika core takes care not to forbid them, either. The same goes for
greenlets, callbacks, continuations, and generators. An instance of Pika's
built-in connection adapters isn't thread-safe, however.
People may be using direct sockets, plain old select(), or any of the
wide variety of ways of getting network events to and from a Python
application. Pika tries to stay compatible with all of these, and to make
adapting it to a new environment as simple as possible.
Documentation
Pika's documentation can be found at https://pika.readthedocs.io.
Example
Here is the most simple example of use, sending a message with the
pika.BlockingConnection adapter:
import pika
connection = pika.BlockingConnection()
channel = connection.channel()
channel.basic_publish(exchange='test', routing_key='test',
body=b'Test message.')
connection.close()
And an example of writing a blocking consumer:
import pika
connection = pika.BlockingConnection()
channel = connection.channel()
for method_frame, properties, body in channel.consume('test'):
# Display the message parts and acknowledge the message
print(method_frame, properties, body)
channel.basic_ack(method_frame.delivery_tag)
# Escape out of the loop after 10 messages
if method_frame.delivery_tag == 10:
break
# Cancel the consumer and return any pending messages
requeued_messages = channel.cancel()
print('Requeued %i messages' % requeued_messages)
connection.close()
Pika provides the following adapters
pika.adapters.asyncio_connection.AsyncioConnection - asynchronous adapter
for Python 3 AsyncIO's
I/O loop.
pika.BlockingConnection - synchronous adapter on top of library for
simple usage.
pika.SelectConnection - asynchronous adapter without third-party
dependencies.
pika.adapters.gevent_connection.GeventConnection - asynchronous adapter
for use with Gevent's I/O loop.
pika.adapters.tornado_connection.TornadoConnection - asynchronous adapter
for use with Tornado's I/O loop.
pika.adapters.twisted_connection.TwistedProtocolConnection - asynchronous
adapter for use with Twisted's I/O loop.
Multiple connection parameters
You can also pass multiple pika.ConnectionParameters instances for
fault-tolerance as in the code snippet below (host names are just examples, of
course). To enable retries, set connection_attempts and retry_delay as
needed in the last pika.ConnectionParameters element of the sequence.
Retries occur after connection attempts using all of the given connection
parameters fail.
import pika
parameters = (
pika.ConnectionParameters(host='rabbitmq.zone1.yourdomain.com'),
pika.ConnectionParameters(host='rabbitmq.zone2.yourdomain.com',
connection_attempts=5, retry_delay=1))
connection = pika.BlockingConnection(parameters)
With non-blocking adapters, such as pika.SelectConnection and
pika.adapters.asyncio_connection.AsyncioConnection, you can request a
connection using multiple connection parameter instances via the connection
adapter's create_connection() class method.
Requesting message acknowledgements from another thread
The single-threaded usage constraint of an individual Pika connection adapter
instance may result in a dropped AMQP/stream connection due to AMQP heartbeat
timeout in consumers that take a long time to process an incoming message. A
common solution is to delegate processing of the incoming messages to another
thread, while the connection adapter's thread continues to service its I/O
loop's message pump, permitting AMQP heartbeats and other I/O to be serviced in
a timely fashion.
Messages processed in another thread may not be acknowledged directly from that
thread, since all accesses to the connection adapter instance must be from a
single thread, which is the thread running the adapter's I/O loop. This is
accomplished by requesting a callback to be executed in the adapter's
I/O loop thread. For example, the callback function's implementation might look
like this:
def ack_message(channel, delivery_tag):
"""Note that `channel` must be the same Pika channel instance via which
the message being acknowledged was retrieved (AMQP protocol constraint).
"""
if channel.is_open:
channel.basic_ack(delivery_tag)
else:
# Channel is already closed, so we can't acknowledge this message;
# log and/or do something that makes sense for your app in this case.
pass
The code running in the other thread may request the ack_message() function
to be executed in the connection adapter's I/O loop thread using an
adapter-specific mechanism:
pika.BlockingConnection abstracts its I/O loop from the application and
thus exposes pika.BlockingConnection.add_callback_threadsafe(). Refer to
this method's docstring for additional information. For example:
connection.add_callback_threadsafe(functools.partial(ack_message, channel, delivery_tag))
When using a non-blocking connection adapter, such as
pika.adapters.asyncio_connection.AsyncioConnection or
pika.SelectConnection, you use the underlying asynchronous framework's
native API for requesting an I/O loop-bound callback from another thread. For
example, pika.SelectConnection's I/O loop provides
add_callback_threadsafe(),
pika.adapters.tornado_connection.TornadoConnection's I/O loop has
add_callback(), while
pika.adapters.asyncio_connection.AsyncioConnection's I/O loop exposes
call_soon_threadsafe().
This threadsafe callback request mechanism may also be used to delegate
publishing of messages, etc., from a background thread to the connection
adapter's thread.
Connection recovery
Some RabbitMQ clients (Bunny, Java, .NET, Objective-C, Swift) provide a way to
automatically recover a connection, its channels and topology (e.g. queues,
bindings and consumers) after a network failure. Others require connection
recovery to be performed by the application code and strive to make it a
straightforward process. Pika falls into the second category.
Pika supports multiple connection adapters. They take different approaches to
connection recovery.
For pika.BlockingConnection adapter exception handling can be used to check
for connection errors. Here is a very basic example:
import pika
while True:
try:
connection = pika.BlockingConnection()
channel = connection.channel()
channel.basic_consume('test', on_message_callback)
channel.start_consuming()
# Don't recover if connection was closed by broker
except pika.exceptions.ConnectionClosedByBroker:
break
# Don't recover on channel errors
except pika.exceptions.AMQPChannelError:
break
# Recover on all other connection errors
except pika.exceptions.AMQPConnectionError:
continue
This example can be found in examples/consume_recover.py.
Generic operation retry libraries such as
retry can be used. Decorators make it
possible to configure some additional recovery behaviours, like delays between
retries and limiting the number of retries:
from retry import retry
@retry(pika.exceptions.AMQPConnectionError, delay=5, jitter=(1, 3))
def consume():
connection = pika.BlockingConnection()
channel = connection.channel()
channel.basic_consume('test', on_message_callback)
try:
channel.start_consuming()
# Don't recover connections closed by server
except pika.exceptions.ConnectionClosedByBroker:
pass
consume()
This example can be found in examples/consume_recover_retry.py.
For asynchronous adapters, use on_close_callback to react to connection
failure events. This callback can be used to clean up and recover the
connection.
An example of recovery using on_close_callback can be found in
examples/asynchronous_consumer_example.py.
Contributing
To contribute to Pika, please make sure that any new features or changes to
existing functionality include test coverage.
Pull requests that add or change code without adequate test coverage will be
rejected.
Additionally, please format your code using
Yapf with google style prior to
issuing your pull request. Note: only format those lines that you have changed
in your pull request. If you format an entire file and change code outside of
the scope of your PR, it will likely be rejected.
Extending to support additional I/O frameworks
New non-blocking adapters may be implemented in either of the following ways:
By subclassing pika.BaseConnection, implementing its abstract method and
passing its constructor an implementation of
pika.adapters.utils.nbio_interface.AbstractIOServices.
pika.BaseConnection implements pika.connection.Connection's abstract
methods, including internally-initiated connection logic. For examples, refer
to the implementations of
pika.adapters.asyncio_connection.AsyncioConnection,
pika.adapters.gevent_connection.GeventConnection and
pika.adapters.tornado_connection.TornadoConnection.
By subclassing pika.connection.Connection and implementing its abstract
methods. This approach facilitates implementation of custom
connection-establishment and transport mechanisms. For an example, refer to
the implementation of
pika.adapters.twisted_connection.TwistedProtocolConnection.
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视频AIGC“王者”Pika诞生，半年估值2亿美元-36氪
视频AIGC“王者”Pika诞生，半年估值2亿美元-36氪
Pika | Small Mammal, High-Altitude Adaptation & Conservation | Britannica
Pika | Small Mammal, High-Altitude Adaptation & Conservation | Britannica
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External Websites
Denali Education Center - Pika
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Denali Education Center - Pika
Alaska Department of Fish and Game - Pika
Animal Diversity Web - Pika
Also known as: Ochotona, coney, cony, little chief hare, mousehare, piping hare, whistling hare
Written by
Andrew T. Smith
Professor of Biology, Arizona State University, U.S. Chairman, Lagomorph Specialist Group, International Union for Conservation of Nature and Natural Resources (IUCN).
Andrew T. Smith
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Table of Contents
pika
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Category:
Animals & Nature
Related Topics:
Koslov’s pika
Ochotona macrotis
northern pika
collared pika
steppe pika
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pika, (genus Ochotona), small short-legged and virtually tailless egg-shaped mammal found in the mountains of western North America and much of Asia. Despite their small size, body shape, and round ears, pikas are not rodents but the smallest representatives of the lagomorphs, a group otherwise represented only by hares and rabbits (family Leporidae).Watch a pika forage for food in mountainous terrain and deliver a litter of fully dependent hairless pupsLearn about the pika (genus Ochotona), including how it maintains a den during the winter and gives birth in the spring.(more)See all videos for this articleThe 29 species of pika are remarkably uniform in body proportions and stance. Their fur is long and soft and is generally grayish-brown in colour, although a few species are rusty red. Unlike those of rabbits and hares, the hind limbs are not appreciably longer than the forelimbs. The feet, including the soles, are densely furred, with five toes in front and four behind. Most pikas weigh between 125 and 200 grams (4.5 and 7.1 ounces) and are about 15 cm (6 inches) in length.
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Animal Factoids
pika sitting on rocksPika (Ochotona) sitting on rocks in North Cascades National Park, Washington, U.S. Pikas are the smallest members of the order Lagomorpha, a group of mammals that also includes rabbits and hares.(more)Survival strategy of the pika in the Sayan MountainsLearn about the pikas in the Sayan Mountains.(more)See all videos for this articlePikas are normally found in mountainous areas at high elevations. Two species reside in North America, the rest being found primarily throughout Central Asia; 23 of them live entirely or partly in China, especially the Tibetan plateau. There are two distinctly different ecological niches occupied by pikas. Some live only in piles of broken rock (talus), whereas others inhabit meadow or steppe environments, where they construct burrows. The North American species and roughly half of the Asian species live in rocky habitats and do not make burrows. Rather, their nests are made deep in a labyrinth of talus adjoining alpine meadows or other suitable vegetation. The collared pika (O. collaris) of Alaska and northern Canada has been found on the isolated nunataks (crags or peaks surrounded by glaciers) in Kluane National Park, and O. macrotis has been recorded at 6,130 metres (20,113 feet) on the slopes of the Himalayas. The pika with the largest distribution, the northern pika (O. hyperborea), ranges from the Ural Mountains to the east coast of Russia and Hokkaido Island of northern Japan. Although the northern pika is considered a typical talus-dwelling species, it also is known to inhabit rocky terrain in coniferous forests, where it makes burrows under fallen logs and tree stumps.There are dramatic differences between pikas that inhabit rocky terrain and those that construct burrows in open habitats. Rock dwellers are generally long-lived (up to seven years) and occur at low density, their populations tending to be stable over time. In contrast, burrowing pikas rarely live more than one year, and their widely fluctuating populations may be 30 or more times as dense. These dense populations fluctuate widely. The contrast between rock-dwelling and burrowing pikas extends to their reproduction. Rock-dwelling pikas normally initiate only two litters per year, and generally only one of these is successfully weaned. It is believed that the second litter is successful only when the first offspring are lost early in the breeding season. Litter size of most rock dwellers is low, but burrowing pikas may produce multiple large litters each season. The steppe pika (O. pusilla) has been reported to have litters of as many as 13 young and breed up to five times in a year.The degree of social behaviour also varies. Rock-dwelling pikas are relatively asocial, claiming widely spaced, scent-marked territories. They communicate their presence to one another by frequently uttering a short call (generally an “eenk” or “ehh-ehh”). Thus, rock-dwelling pikas are able to keep track of neighbours, directly encountering them only once or twice a day. Such encounters normally result in aggressive chases. In contrast, burrowing pikas live in family groups, and these groups occupy and defend a mutual territory. Within the group, social encounters are numerous and generally amicable. Pikas of all ages and both sexes may groom each other, rub noses, or sit side-by-side. Aggressive encounters, normally in the form of long chases, ensue only when an individual from one family group trespasses on the territory of another. Burrowing pikas also have a much larger vocal repertoire than rock-dwelling pikas. Many of these calls signal cohesion within family groups, especially among young from sequential litters or between males and juveniles. All pikas utter short alarm calls when predators are sighted. Males give a long call, or song, during the mating season.Unlike rabbits and hares, pikas are active during the day, with the exception of the nocturnal steppe pikas (O. pusilla). Being largely alpine or boreal species, most pikas are adapted to living in cold environments and cannot tolerate heat. When temperatures are high, they confine their activity to early morning and late afternoon. Pikas do not hibernate, and they are generalized herbivores. Where snow blankets their environment (as is often the case), they construct caches of vegetation called haypiles to provide food during winter. A characteristic behaviour of rock-dwelling pikas during summer is their repeated trips to meadows adjoining the talus to harvest plants for the haypile. One often repeated but untrue tale is that pikas lay their hay on rocks to dry before storing it. Rather, pikas carry their provisions straight to their haypile unless disturbed. Similar to other lagomorphs, pikas practice coprophagy (see rabbit) to provide additional vitamins and nutrients from their relatively poor-quality forage.
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Most pikas live in areas far away from people, yet, given the high densities reached by some burrowing pikas, they have been considered pests on the Tibetan plateau, where pikas are thought to reduce forage for domestic livestock and to damage grasslands. In response, government agencies in China have poisoned them over great expanses. Recent analyses, however, have shown that such control efforts may be misguided, as the pika is a keystone species for biodiversity in this region. Four Asian pikas—three in China and one in Russia and Kazakhstan—are listed as endangered species. One of these, Koslov’s pika (O. koslowi) from China, was originally collected by the Russian explorer Nikolai Przewalski in 1884, and approximately 100 years passed before it was seen again. Not only is this species apparently rare, but it may be in danger of being poisoned as part of control efforts directed at plateau pikas.
Pikas have a variety of common names, most applied to particular forms or species. The names mouse hare and cony are sometimes used, although the pika is neither mouse nor hare, and cony may be confused with the unrelated hyrax—the biblical coney. The genus name originates from the Mongolian ochodona, and the term pika comes from the vernacular piika of the Tunguses, a tribe from northeastern Siberia. Ochotona is the sole living genus of the family Ochotonidae, and its members lack several special skeletal modifications present in hares and rabbits (family Leporidae), such as a highly arched skull, relatively upright posture of the head, strong hind limbs and pelvic girdle, and elongation of limbs. The family Ochotonidae was clearly differentiated from the other lagomorphs as early as the Oligocene Epoch. Ochotona first appeared in the fossil record in the Pliocene in eastern Europe, Asia, and western North America. Its origin was probably in Asia. By the Pleistocene, Ochotona was found in the eastern United States and as far west in Europe as Great Britain. This extensive spread was followed by restriction to its present range. One fossil pika (genus Prolagus) apparently lived during historical time. Its remains have been found on Corsica, Sardinia, and adjacent small islands. Earlier fossil material has been found on the mainland of Italy. Apparently it was still present up to 2,000 years ago but was driven to extinction, likely owing to habitat loss and to competition and predation from introduced animals.
Andrew T. Smith
AI 视频生成工具 Pika 爆火，学霸创始人被评近乎完美，其父亲还有家上市公司，哪些信息值得关注？ - 知乎
AI 视频生成工具 Pika 爆火，学霸创始人被评近乎完美，其父亲还有家上市公司，哪些信息值得关注？ - 知乎首页知乎知学堂发现等你来答切换模式登录/注册互联网人工智能投资商业股票AI 视频生成工具 Pika 爆火，学霸创始人被评近乎完美，其父亲还有家上市公司，哪些信息值得关注？每日经济新闻已认证账号11月30日，信雅达（600571.SH，股价11.04元，市值51.53亿元）股价大涨，截至收盘报11.04元/股，上涨9.96%。在相关股票论坛，…显示全部 关注者878被浏览1,921,031关注问题写回答邀请回答好问题 831 条评论分享254 个回答默认排序啤酒橘子Virtus科技，游戏，键政，情感，职场，亲子，PPT，故事，我都不会。 关注刚在主页登陆，居然需要等待？？？？？几乎所有地方都找不到这个东西的真身。却有一个热搜。炒作的性质显而易见。前排的答案更是机构操作，这年代关注几个真人多重要啊。我是很相信未来大家只要写一本小说就能出现连续剧。问题是不是今天啊。更：已被测试，Discord上的阉割版是垃圾。大家都可以搜索上手，不过纯粹浪费时间。正式版不会有突破进展，几个月的项目，从测试到正式直接上天？编辑于 2023-12-01 14:00赞同 107457 条评论分享收藏喜欢收起知乎用户我测试了一下他们的模型，并看了几个类似的测试，只能说离他们的宣传片差的有点远。虽然这个不是他们口中的1.0版本，但我依然觉得视频中的效果，很难使我相信。下面几个视频：A lovely girl is dancingpeople running in the city at nighta cute garfield cat walks on the beach on a sunny dayPika生成：一个可爱的女孩跳舞https://www.zhihu.com/video/1713890779184087040Pika生成：夜晚人们在城市中跑https://www.zhihu.com/video/1713889082189639680Pika生成：加菲猫走在沙滩上https://www.zhihu.com/video/1713889433781379072我总体的看法是：这个团队的技术能力有待验证，营销能力是满分的。现在点开官网发现也只是进了一个 waitlist。这波先把流量获取了，走在技术的前面。然后再一点点补足技术的短板。不得不说这个团队是有炒作的土壤的。高学历+高颜值+女生+天才，天然具有话题度。但是新闻中说的4个人6个月做出来，有点离谱的感觉。新闻中唯一让我惊讶的只有一个：4个人的团队能够融到5000万美元。美国的投资圈这么热情吗？编辑于 2023-12-01 13:40赞同 21538 条评论分享收藏喜欢