{"id":15550,"date":"2016-08-15T17:06:38","date_gmt":"2016-08-15T21:06:38","guid":{"rendered":"http:\/\/mjtsai.com\/blog\/?p=15550"},"modified":"2016-08-21T13:03:01","modified_gmt":"2016-08-21T17:03:01","slug":"why-dont-podcasts-use-vbr-mp3s","status":"publish","type":"post","link":"https:\/\/mjtsai.com\/blog\/2016\/08\/15\/why-dont-podcasts-use-vbr-mp3s\/","title":{"rendered":"Why Don&rsquo;t Podcasts Use VBR MP3s?"},"content":{"rendered":"<p><a href=\"https:\/\/marco.org\/2016\/08\/15\/vbr-mp3-plea\">Marco Arment<\/a> (<a href=\"https:\/\/news.ycombinator.com\/item?id=12292411\">Hacker News<\/a>):<\/p>\n<blockquote cite=\"https:\/\/marco.org\/2016\/08\/15\/vbr-mp3-plea\"><p>AVFoundation, the low-level audio\/video framework in iOS and macOS, does not accurately seek within <a href=\"https:\/\/en.wikipedia.org\/wiki\/Variable_bitrate\">VBR<\/a> MP3s, making VBR impractical to use for long files such as podcasts. Jumping to a timestamp in an hour-long VBR podcast can result in an error of over a minute, without the listener even knowing because the displayed timecode shows the expected time.<\/p>\n<p>[&#8230;]<\/p>\n<p>Three simple solutions to accurate VBR stream-seeking have existed for almost twenty years to embed seek-offset tables at the start of VBR MP3s for precise seeking[&#8230;] But AVFoundation supports none of them.<\/p><\/blockquote>\n<p>Update (2016-08-21): See also: <a href=\"http:\/\/atp.fm\/episodes\/183\">Accidental Tech Podcast<\/a>.<\/p>","protected":false},"excerpt":{"rendered":"<p>Marco Arment (Hacker News): AVFoundation, the low-level audio\/video framework in iOS and macOS, does not accurately seek within VBR MP3s, making VBR impractical to use for long files such as podcasts. Jumping to a timestamp in an hour-long VBR podcast can result in an error of over a minute, without the listener even knowing because [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"apple_news_api_created_at":"","apple_news_api_id":"","apple_news_api_modified_at":"","apple_news_api_revision":"","apple_news_api_share_url":"","apple_news_coverimage":0,"apple_news_coverimage_caption":"","apple_news_is_hidden":false,"apple_news_is_paid":false,"apple_news_is_preview":false,"apple_news_is_sponsored":false,"apple_news_maturity_rating":"","apple_news_metadata":"\"\"","apple_news_pullquote":"","apple_news_pullquote_position":"","apple_news_slug":"","apple_news_sections":"\"\"","apple_news_suppress_video_url":false,"apple_news_use_image_component":false,"footnotes":""},"categories":[2],"tags":[95,273,131,31,1137,30,1199,112],"class_list":["post-15550","post","type-post","status-publish","format-standard","hentry","category-technology","tag-audio","tag-avfoundation","tag-bug","tag-ios","tag-ios-9","tag-mac","tag-mac-os-x-10-11","tag-podcasts"],"apple_news_notices":[],"_links":{"self":[{"href":"https:\/\/mjtsai.com\/blog\/wp-json\/wp\/v2\/posts\/15550","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mjtsai.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mjtsai.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mjtsai.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/mjtsai.com\/blog\/wp-json\/wp\/v2\/comments?post=15550"}],"version-history":[{"count":2,"href":"https:\/\/mjtsai.com\/blog\/wp-json\/wp\/v2\/posts\/15550\/revisions"}],"predecessor-version":[{"id":15634,"href":"https:\/\/mjtsai.com\/blog\/wp-json\/wp\/v2\/posts\/15550\/revisions\/15634"}],"wp:attachment":[{"href":"https:\/\/mjtsai.com\/blog\/wp-json\/wp\/v2\/media?parent=15550"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mjtsai.com\/blog\/wp-json\/wp\/v2\/categories?post=15550"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mjtsai.com\/blog\/wp-json\/wp\/v2\/tags?post=15550"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}