From patchwork Fri Oct 21 12:56:03 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: James Almer X-Patchwork-Id: 38864 Delivered-To: ffmpegpatchwork2@gmail.com Received: by 2002:a05:6a20:4a86:b0:9d:28a3:170e with SMTP id fn6csp756335pzb; Fri, 21 Oct 2022 05:56:42 -0700 (PDT) X-Google-Smtp-Source: AMsMyM71PFERkqqfpWnVpG0b0urYoR49UvBDZqmIFy1Rqc8VdxI5VUvk2+YcOtdx+DqVC/UZ+KUN X-Received: by 2002:a05:6402:2694:b0:45c:a035:34bc with SMTP id w20-20020a056402269400b0045ca03534bcmr16872922edd.158.1666357002498; Fri, 21 Oct 2022 05:56:42 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1666357002; cv=none; d=google.com; s=arc-20160816; b=oX6w3EQEFMCV8UcKkeMXJfUjkHu0MMwk8k9TBeaegO45q2tneoaxyDt+2p8fagCL/V NznDbYmHDrDjmuy4ni+9VKxha07QtKkLa3CNZ4gm/zOQPSgzwGE65RR7QPv8x5pf/N68 E0pryM5h+vgpDEFzZFLpjZ1z+BTdoHFpsd63vX8mVfApNrrw03qndJuS4K3ri15MmxaE vskw13aB51hQxTZZGE9ZJHfU9SXxfn62utW6lyjPtZ5BqntkJw/z57PQe/x4/Ec4Sv4L Z3DB49fOSeVAx/IOC3ZZCCtXh69fXa06iGkCRfidsRkPErC0DSoRnNltIW5H4FH5HB+8 J4gQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=sender:errors-to:content-transfer-encoding:reply-to:list-subscribe :list-help:list-post:list-archive:list-unsubscribe:list-id :precedence:subject:mime-version:message-id:date:to:from :dkim-signature:delivered-to; bh=E/VD7lOLeZBItNSIkmq54Ey5xDUSqoeGaTTfAwWf9os=; b=LAuLLtvqcVxHu5d14cPAJSr3WErMVzw9BZAwEngJJUrVRRkaChS5TrPBGAy+nu1Luw iDdtoazYKPiLSegfjUp/WoU47X23B80/Y/g9/5cBWeQICyqaC7R1Y0mbB6gnsAUEQDPg cpZ3R3xZkmdzi2Fe360DnDap85JffyffFUPzL46/HbEvuUXNf5aOhII1g+bvSALk1YP2 SGL+M2fiuG1VEpnjoU5ciWwvWXhIZqzsNxkOI+t1qOx7arA9w4PJnkqTPi1Se69yOawp zBQOAUtuxle3Lu1rBJFioODpl8q02bs7bvsH4d6TAEQ4HybHRd/5w/2q6Pl7M3bdd5P/ IO3Q== ARC-Authentication-Results: i=1; mx.google.com; dkim=neutral (body hash did not verify) header.i=@gmail.com header.s=20210112 header.b=CaREaCW6; spf=pass (google.com: domain of ffmpeg-devel-bounces@ffmpeg.org designates 79.124.17.100 as permitted sender) smtp.mailfrom=ffmpeg-devel-bounces@ffmpeg.org; dmarc=fail (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Return-Path: Received: from ffbox0-bg.mplayerhq.hu (ffbox0-bg.ffmpeg.org. [79.124.17.100]) by mx.google.com with ESMTP id e22-20020a1709067e1600b0073da5c8de1asi19006108ejr.178.2022.10.21.05.56.41; Fri, 21 Oct 2022 05:56:42 -0700 (PDT) Received-SPF: pass (google.com: domain of ffmpeg-devel-bounces@ffmpeg.org designates 79.124.17.100 as permitted sender) client-ip=79.124.17.100; Authentication-Results: mx.google.com; dkim=neutral (body hash did not verify) header.i=@gmail.com header.s=20210112 header.b=CaREaCW6; spf=pass (google.com: domain of ffmpeg-devel-bounces@ffmpeg.org designates 79.124.17.100 as permitted sender) smtp.mailfrom=ffmpeg-devel-bounces@ffmpeg.org; dmarc=fail (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 385D468BE86; Fri, 21 Oct 2022 15:56:39 +0300 (EEST) X-Original-To: ffmpeg-devel@ffmpeg.org Delivered-To: ffmpeg-devel@ffmpeg.org Received: from mail-ot1-f54.google.com (mail-ot1-f54.google.com [209.85.210.54]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id 5A86068BE70 for ; Fri, 21 Oct 2022 15:56:33 +0300 (EEST) Received: by mail-ot1-f54.google.com with SMTP id a16-20020a056830101000b006619dba7fd4so1731842otp.12 for ; Fri, 21 Oct 2022 05:56:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:message-id:date:subject:to :from:from:to:cc:subject:date:message-id:reply-to; bh=a6pYP/71ctfYApUoRrig6GwLL3ZMtAWvPyIBht6Fydc=; b=CaREaCW6L5TdAgsQzFDwAiaQ/5eR3oRMF9D7e1rEvRanal3x4JhLFVYMVHCqJKHdMN XzKxq7qz5ycrHfAKSltXzUHaZH1lZA4t2LYzGXzA4a0Ggckg4kRBWkEJF8KqTG1ZXoWp +9dpZStFjrDHCt+RTTGtaJ2FjycoDm5Ud31J5H+okn8Rkk0j5KxYkjNKGrLNSH/z46mn 5U+VqlIj7D8wsPGz6QzHrBuMQB6lbiwAET3vczMelYTFgsSFrPNlWB/HENeCV6GVjtJA 6TfIIuWy4hhaY2M2gJJDSTJcJW+9slsYlTCokx4h2mgas/8TynA1WGPziOAhVYw2Pa2G HKyg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:message-id:date:subject:to :from:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=a6pYP/71ctfYApUoRrig6GwLL3ZMtAWvPyIBht6Fydc=; b=tYAkLbX5oa+77EAhXi5tBB8UC8tlxEQOT7862VrNg3lGfDME7gQyIBXMD/lh6RIW9Y Y51DSf5c5gM8OEaKxj9m7IOUFfzAg4TXicm7e8/KFNYqGUw0SRtlcM1jEZW5SOmAThby lCASMm52t/mouOvJpLeujdEc1fkpXxS8XTjydDyvOWjdHIFhnCziUhJwhKKQy0FFQOHJ 0CNsm9pf3rJxRcVgKhr34VrYrvxOHrQJ5g0tDRvplXJQW/Jv/5tDQzmQl4WTkLVOMN9p bMSfDYgE9XW3DPrblLvuvpeXp3L+yvsb91A2m03AQsd5fECgxPnhCN5okKChRYfdl52Q sVKQ== X-Gm-Message-State: ACrzQf190otDTAeQWoxTikTIim1NP9WaWdVLHx57HPcikxZ2Q0eSzQlO a8pDvrZEkI9NKmvtRONW6fXpR4J9OLM= X-Received: by 2002:a9d:6f02:0:b0:661:d432:fb52 with SMTP id n2-20020a9d6f02000000b00661d432fb52mr9984114otq.153.1666356991376; Fri, 21 Oct 2022 05:56:31 -0700 (PDT) Received: from localhost.localdomain ([191.97.187.183]) by smtp.gmail.com with ESMTPSA id s17-20020a4ac811000000b00480dccc0c2asm3735994ooq.14.2022.10.21.05.56.30 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 21 Oct 2022 05:56:31 -0700 (PDT) From: James Almer To: ffmpeg-devel@ffmpeg.org Date: Fri, 21 Oct 2022 09:56:03 -0300 Message-Id: <20221021125604.1107-1-jamrial@gmail.com> X-Mailer: git-send-email 2.37.3 MIME-Version: 1.0 Subject: [FFmpeg-devel] [PATCH 1/2] avcodec/ac3dec: split off code discarding garbage at the beginning of a packet X-BeenThere: ffmpeg-devel@ffmpeg.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: FFmpeg development discussions and patches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: FFmpeg development discussions and patches Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" X-TUID: 72f0OhtsFSWD Signed-off-by: James Almer --- libavcodec/ac3_parser.c | 19 +++++++++++++++++++ libavcodec/ac3_parser_internal.h | 2 ++ libavcodec/ac3dec.c | 15 ++------------- 3 files changed, 23 insertions(+), 13 deletions(-) diff --git a/libavcodec/ac3_parser.c b/libavcodec/ac3_parser.c index 4f154bb7c4..425e1b4742 100644 --- a/libavcodec/ac3_parser.c +++ b/libavcodec/ac3_parser.c @@ -53,6 +53,25 @@ static const uint8_t center_levels[4] = { 4, 5, 6, 5 }; */ static const uint8_t surround_levels[4] = { 4, 6, 7, 6 }; +int ff_ac3_find_syncword(const uint8_t *buf, int buf_size) +{ + int i; + + for (i = 1; i < buf_size; i += 2) { + if (buf[i] == 0x77 || buf[i] == 0x0B) { + if ((buf[i] ^ buf[i-1]) == (0x77 ^ 0x0B)) { + i--; + break; + } else if ((buf[i] ^ buf[i+1]) == (0x77 ^ 0x0B)) { + break; + } + } + } + if (i >= buf_size) + return AVERROR_INVALIDDATA; + + return i; +} int ff_ac3_parse_header(GetBitContext *gbc, AC3HeaderInfo *hdr) { diff --git a/libavcodec/ac3_parser_internal.h b/libavcodec/ac3_parser_internal.h index bd4e1bbffb..2ac0e67ec2 100644 --- a/libavcodec/ac3_parser_internal.h +++ b/libavcodec/ac3_parser_internal.h @@ -79,4 +79,6 @@ int ff_ac3_parse_header(GetBitContext *gbc, AC3HeaderInfo *hdr); int avpriv_ac3_parse_header(AC3HeaderInfo **hdr, const uint8_t *buf, size_t size); +int ff_ac3_find_syncword(const uint8_t *buf, int buf_size); + #endif /* AVCODEC_AC3_PARSER_INTERNAL_H */ diff --git a/libavcodec/ac3dec.c b/libavcodec/ac3dec.c index 340f6e1e37..8e40587ff1 100644 --- a/libavcodec/ac3dec.c +++ b/libavcodec/ac3dec.c @@ -1508,19 +1508,8 @@ static int ac3_decode_frame(AVCodecContext *avctx, AVFrame *frame, s->superframe_size = 0; buf_size = full_buf_size; - for (i = 1; i < buf_size; i += 2) { - if (buf[i] == 0x77 || buf[i] == 0x0B) { - if ((buf[i] ^ buf[i-1]) == (0x77 ^ 0x0B)) { - i--; - break; - } else if ((buf[i] ^ buf[i+1]) == (0x77 ^ 0x0B)) { - break; - } - } - } - if (i >= buf_size) - return AVERROR_INVALIDDATA; - if (i > 10) + i = ff_ac3_find_syncword(buf, buf_size); + if (i < 0 || i > 10) return i; buf += i; buf_size -= i;