視頻會議的迭代方向是打造更好的“臨場感”

{"type":"doc","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"2020年，突如其來的新冠肺炎疫情改變了許多人的生活和工作方式。疫情之下，RTC（實時音視頻）產品受到越來越多的關注，用戶對產品的質量也有着越來越高的要求。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"“以往傳統視頻會議產品更側重於大企業內部使用，形態上專用設備和PC端居多。疫情讓所有企業，特別是中小微企業，對遠程辦公，視頻會議產品有了廣泛的需求，使用場景與之前相比也更爲複雜，不再侷限於辦公場所的開會，而是要求能夠隨時隨地便捷接入通訊，終端也從企業級設備、PC向移動電話延伸。”近日，騰訊會議高級工程師趙珺接受InfoQ採訪，就音視頻的發展現狀、不足以及改進方向等話題展開討論。他表示，視頻會議產品的迭代方向主要是針對這類複雜場景打造更好的“臨場感”。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"5月29日，趙珺將於QCon 全球軟件開發大會（北京站）的《音視頻體驗提升實戰》專題中，帶來“音視頻QoE優化工作的難點與挑戰”的分享。希望借本次分享系統闡述RTC領域質量工作所面臨的問題及難點，並結合在騰訊會議產品上的實踐來介紹利用現網數據優化用戶QoE的思考與成果。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"以下是InfoQ與趙珺的對話紀要："}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"InfoQ：後疫情時代，遠程會議工作模式越來越被接納，而隨着需求激增，視頻會議產品也需要推陳出新，在您看來，從新冠疫情最初爆發至今，像視頻會議這類音視頻產品的更新迭代主要側重在哪些方面？"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"趙珺：以往傳統視頻會議產品更側重於大企業內部使用，形態上專用設備和PC端居多。去年年初疫情的突然爆發，讓所有企業，特別是中小微企業對於遠程辦公，視頻會議產品有了廣泛的需求，使用場景與之前相比也更爲複雜，不再侷限於辦公場所的開會，而是要求能夠隨時隨地的便捷接入通訊，終端也從企業級設備，PC向移動電話延伸。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"視頻會議產品的迭代方向主要是針對這類複雜場景打造更好的“臨場感”。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"首先從技術上說，會利用更優秀的網絡抗性策略，更強大的語音降噪、回聲消除能力等技術降低使用環境複雜化所帶來的影響。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"其次，針對不同的客戶場景，如何貼近真實開會體驗也是一個比較重要的問題，比如針對隱私需求的背景虛化能力，針對重要會議場景的等候室能力，針對交流討論場景的白板能力，針對培訓場景的錄製能力等，都是讓用戶一方面體驗線上會議的優勢，另一方面降低無法現場交流的不便。"}]}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"InfoQ：您如何看待現階段音視頻對質量的要求？能否結合音視頻體驗的發展趨勢展開聊聊。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"趙珺：與單純的文字相比，音視頻是人類視覺和聽覺可以直接觸達的媒體，人們對於音視頻的主觀評價會更爲直接，對音視頻產品的體驗要求也是逐步提高的。以視頻爲例，幾十年前，一個小小的黑白電視就能滿足需求，而後的彩色電視，高清格式，4K格式， HDR等技術升級都在提升着對於視頻體驗的心理預期。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"所以說人們對於音視頻的體驗需求是沒有上限的，但是卻有下限，那就是保持信息的有效傳遞。設想一下，如果出現火災，打不通電話，或打通了說不清楚信息，後果將是災難性的。"}]}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"InfoQ：面對音視頻服務的不同發展階段，後臺技術支撐框架發生了什麼樣的變化？"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"趙珺：互聯網音視頻業務大體可分爲點播，直播，RTC三個階段。首先是點播業務，比如我們常用追劇的騰訊視頻、愛奇藝更多的是關注視頻流的快速送達，所以後臺上多廣泛使用CDN節點；"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"其次是直播業務，在點播業務的基礎之上，爲追求清晰度與流暢度體驗的平衡，往往還會引入轉碼服務器，對於傳輸協議也有較多的個性化需求，需要後臺來配合處理；"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"最後是RTC業務，與前兩者相比，其對於傳輸RTT的要求會更高，後臺結構也相對更復雜，會有流控，房間管理，混音等不同的服務類型來共同工作。"}]}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"InfoQ：能否介紹下目前音視頻產品的質量工作流程一般是怎麼樣的？"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"趙珺：以我們爲例，目前的工作流程主要分爲上線前測試和上線後質量管理兩個部分。上線前會針對技術優化的一些點來針對性進行評測，評測標準主要參考了ITU， 3GPP這些組織的一些音視頻相關國際標準。特性上線後，會通過產品的灰度策略，來進行A\/B Test 評估優化是否是正向的。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"我們還有多維度的大盤質量報表，藉助大量用戶數據來評估產品質量的變化趨勢，以此來發現問題和持續改進。"}]}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"InfoQ：像直播中碰到卡頓、實時音視頻通話延遲等情況，一般的解決方法是什麼？隨着用戶體驗要求越來越高，互動性也不斷加大，對你們來說，這裏面的挑戰也會越來越大，能否展開介紹下這過程中面臨的技術問題和挑戰？"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"趙珺：網絡帶寬是有限的，直播卡頓，語音延遲這些問題多數時候是帶寬競爭下所產生的結果。應該從兩個維度來考慮解決。第一是編碼器、傳輸協議是否有優化的空間，壓縮碼流體積，減少不必要的傳輸開銷是根本。如果編碼器和協議的選擇已經相對較優了，下一步可以嘗試的方案就是一個做取捨的策略問題，高清、流暢、低延遲三者不可兼得，應當根據業務場景做出必要的取捨。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"所以這裏最主要的挑戰應該是編碼器的優化，傳輸協議的優化和帶寬探測幾個方面。高效編碼能讓碼流更小，高效傳輸能讓帶寬浪費更低，準確預測帶寬能讓分配策略更合理。"}]}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"InfoQ：怎麼利用用戶數據確定音視頻產品的改進方向？能否結合實際案例跟我們介紹下？"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"趙珺：爲了提升用戶體驗，騰訊會議引入了媒體代理的架構，由分佈在全球的代理節點來爲用戶提供“就近進入”的服務。如何評價用戶接入分配的合理性是一個困擾團隊的問題。我們通過對現網QoE用戶數據的分析，不僅發現了某地運營商機房的問題， 還得出“最近接入” 並非 “最優接入” 的結論，指導全球接入調度的優化。這個案例也會在本次大會演講上分享。"}]}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"InfoQ：據您觀察，現在的音視頻產品還存在哪些不足？未來音視頻產品有哪些可能的改進方向？"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"趙珺：現有音視頻產品是個比較大的命題，受限經驗，不敢妄談。 還是說一下比較瞭解的RTC業務。從體驗角度上來說，RTC的追求目標是“身前1米”的面對面交流的體驗，現在很多時候還是難以滿足的。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"伴隨着5G時代的到來，未來音視頻產品會對沉浸式體驗的需求將更強，VR、AR一類的技術也會是音視頻產品新的載體，因此對於編碼壓縮，傳輸，視頻高效轉碼，視頻處理，語音降噪等技術都將會有更高的要求。"}]}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"InfoQ：總的來看，面對前面提到的問題和挑戰，您認爲這裏邊需要什麼樣的體驗質量優化體系？"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"趙珺：音視頻體驗是技術、人的生理、心理多因素共同作用的結果。音視頻體驗的評價不單是工業界關心的問題，也是學術界的研究熱點之一。現有評價體系侷限性還很強，所以對於評價方法的探索是質量優化體系建設最爲重要的一環。另一方面，建立完備的，可以覆蓋不同用戶設備，不同用戶場景的質量數據體系也是質量優化建設的努力方向。"}]}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"InfoQ：在您看來，除了技術方面，QoE是否也屬於管理問題？"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"趙珺：答案是肯定的，QoE本質是一個預期管理的問題，當技術無法滿足預期時，最好的方法是降低用戶預期，比如在網絡差時的一些告知tips, 會起到很好的效果。當然，有些場景下的用戶預期管理可能比技術本身難度更高。"}]}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"InfoQ：最後，能否說說咱們對未來音視頻業務體驗的規劃方向是怎麼樣的？"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"趙珺：質量管理方面，除了對於評價標準的持續探索外，未來我們會投入更多的精力在實時監控，問題發現上，爲用戶使用騰訊會議提供更高級別的質量保障；"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"音視頻技術上，相關團隊也在加大對於音頻降噪，回聲消除，網絡傳輸優化，視頻編解碼等技術方向的投入，在爲會議產品服務的同時，也將成果輸出給其他領域產品。"}]}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"採訪嘉賓介紹"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"趙珺，騰訊會議高級工程師，研究生畢業後先後於華爲和騰訊任職。在騰訊6年多的時間裏，歷經QQ音視頻，互動直播SDK，遊戲語音引擎，騰訊無線投屏，騰訊會議多個實時音視頻產品的質量保證和優化工作，在RTC產品測試和基於QoE的監控分析方面有豐富的經驗。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"活動推薦"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"趙珺將在今年 5 月 29-31 日舉辦的 QCon 全球軟件開發大會（北京站）「音視頻體驗提升實戰」專場，發佈《音視頻QoE優化工作的難點與挑戰》的演講，將系統闡述 RTC 領域質量工作所面臨的問題及難點，並結合在騰訊會議產品上的實踐來介紹利用現網數據優化用戶 QoE 的思考與成果。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"QCon大會北京站匯聚 150+ 演講嘉賓，同時設立 29 個熱點技術專場包括 Serverless、Flutter、DDD、音視頻、雲原生、智能金融、大數據、數字化轉型、人工智能等，內容源於實踐並面向社區。【掃碼】或"},{"type":"link","attrs":{"href":"https:\/\/qcon.infoq.cn\/2021\/beijing\/schedule?utm_source=infoq&utm_medium=article&utm_campaign=10&utm_term=0514&utm_content=banner","title":"xxx","type":null},"content":[{"type":"text","text":"點此"}]},{"type":"text","text":"瞭解更多。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"今天是大會門票"},{"type":"text","marks":[{"type":"color","attrs":{"color":"#F5222D","name":"red"}}],"text":" 9 "},{"type":"text","text":"折特惠倒計時最後 1 天，現在購票立減"},{"type":"text","marks":[{"type":"color","attrs":{"color":"#F5222D","name":"red"}}],"text":" 880 "},{"type":"text","text":"元。購票歡迎聯繫票務小姐姐 Doris ：17310043226（電話同微信）"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"image","attrs":{"src":"https:\/\/static001.infoq.cn\/resource\/image\/b1\/2b\/b13ee664ebe4efef0b7e2cf8d497c42b.jpeg","alt":null,"title":"","style":[{"key":"width","value":"75%"},{"key":"bordertype","value":"none"}],"href":"","fromPaste":false,"pastePass":false}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}}]}