From patchwork Tue May 12 13:44:21 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Fu, Linjie" X-Patchwork-Id: 19647 Return-Path: X-Original-To: patchwork@ffaux-bg.ffmpeg.org Delivered-To: patchwork@ffaux-bg.ffmpeg.org Received: from ffbox0-bg.mplayerhq.hu (ffbox0-bg.ffmpeg.org [79.124.17.100]) by ffaux.localdomain (Postfix) with ESMTP id 1265544BCFF for ; Tue, 12 May 2020 16:46:39 +0300 (EEST) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id E15D5689A91; Tue, 12 May 2020 16:46:38 +0300 (EEST) X-Original-To: ffmpeg-devel@ffmpeg.org Delivered-To: ffmpeg-devel@ffmpeg.org Received: from mga17.intel.com (mga17.intel.com [192.55.52.151]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id 94907689924 for ; Tue, 12 May 2020 16:46:32 +0300 (EEST) IronPort-SDR: LENw0IvTEQhRY28RzMTcVzgYfMuMAX1XP98LSeoN7Mb3u5R6FdAfly7y/dmW3THpgpMHIFM9mB 7U3pW1i6ZZiw== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga006.jf.intel.com ([10.7.209.51]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 May 2020 06:46:30 -0700 IronPort-SDR: dt0+sCxoBrm033RT4T0FBU1N4WOfq+TPAhY8OtnhGlXBDxzv8FAmHlbU0Lha8ZrkEnOG6VgcDd /YXjtR3cdykA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.73,383,1583222400"; d="scan'208";a="265509560" Received: from icl-dev.sh.intel.com ([10.239.158.73]) by orsmga006.jf.intel.com with ESMTP; 12 May 2020 06:46:28 -0700 From: Linjie Fu To: ffmpeg-devel@ffmpeg.org Date: Tue, 12 May 2020 21:44:21 +0800 Message-Id: <1589291061-4348-1-git-send-email-linjie.fu@intel.com> X-Mailer: git-send-email 2.7.4 Subject: [FFmpeg-devel] [PATCH 2/2] lavc/hevc_refs: Fix the logic of find_ref_idx() X-BeenThere: ffmpeg-devel@ffmpeg.org X-Mailman-Version: 2.1.20 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 Cc: Xu Guangxin , Linjie Fu MIME-Version: 1.0 Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" From: Xu Guangxin Currently find_ref_idx() would trigger 2 scans in DPB to find the requested POC: 1. Firstly, ignore MSB of ref->poc and search for the requested POC; 2. Secondly, compare the entire ref->poc with requested POC; For long term reference, we are able to only check LSB if MSB is not presented(e.g. delta_poc_msb_present_flag == 0). However, for short term reference, we should never ignore poc's MSB and it should be kind of bit-exact. (Details in 8.3.2) Otherwise this leads to decoding failures like: [hevc @ 0x5638f4328600] Error constructing the frame RPS. [hevc @ 0x5638f4328600] Error parsing NAL unit #2. [hevc @ 0x5638f4338a80] Could not find ref with POC 21 Error while decoding stream #0:0: Invalid data found when processing input Search the requested POC based on whether MSB is used, and avoid the 2-times scan for DPB buffer. This benefits both native HEVC decoder and integrated HW decoders. Signed-off-by: Linjie Fu --- Since it's kind of difficult to generate an identical bitstream for fate or test, I'd like to elaborate more about one of the failures: requested POC = 5; LtMask = (1 << 4) - 1 = 15; ref[0]->poc = 21; // unexpected ref for poc = 5 (short term) ref[1]->poc = 5; // expected ref for poc = 5 (short term) Hence find_ref_idx() would wrongly return a ref with poc = 21, which leads to the decoding error. libavcodec/hevc_refs.c | 38 ++++++++++++++++++++------------------ 1 file changed, 20 insertions(+), 18 deletions(-) diff --git a/libavcodec/hevc_refs.c b/libavcodec/hevc_refs.c index 7870a72..73aa6d8 100644 --- a/libavcodec/hevc_refs.c +++ b/libavcodec/hevc_refs.c @@ -358,24 +358,26 @@ int ff_hevc_slice_rpl(HEVCContext *s) return 0; } -static HEVCFrame *find_ref_idx(HEVCContext *s, int poc) +static HEVCFrame *find_ref_idx(HEVCContext *s, int poc, uint8_t use_msb) { int i; - int LtMask = (1 << s->ps.sps->log2_max_poc_lsb) - 1; - for (i = 0; i < FF_ARRAY_ELEMS(s->DPB); i++) { - HEVCFrame *ref = &s->DPB[i]; - if (ref->frame->buf[0] && (ref->sequence == s->seq_decode)) { - if ((ref->poc & LtMask) == poc) - return ref; + if (use_msb) { + for (i = 0; i < FF_ARRAY_ELEMS(s->DPB); i++) { + HEVCFrame *ref = &s->DPB[i]; + if (ref->frame->buf[0] && (ref->sequence == s->seq_decode)) { + if (ref->poc == poc) + return ref; + } } - } - - for (i = 0; i < FF_ARRAY_ELEMS(s->DPB); i++) { - HEVCFrame *ref = &s->DPB[i]; - if (ref->frame->buf[0] && ref->sequence == s->seq_decode) { - if (ref->poc == poc || (ref->poc & LtMask) == poc) - return ref; + } else { + int LtMask = (1 << s->ps.sps->log2_max_poc_lsb) - 1; + for (i = 0; i < FF_ARRAY_ELEMS(s->DPB); i++) { + HEVCFrame *ref = &s->DPB[i]; + if (ref->frame->buf[0] && ref->sequence == s->seq_decode) { + if ((ref->poc & LtMask) == poc) + return ref; + } } } @@ -427,9 +429,9 @@ static HEVCFrame *generate_missing_ref(HEVCContext *s, int poc) /* add a reference with the given poc to the list and mark it as used in DPB */ static int add_candidate_ref(HEVCContext *s, RefPicList *list, - int poc, int ref_flag) + int poc, int ref_flag, uint8_t use_msb) { - HEVCFrame *ref = find_ref_idx(s, poc); + HEVCFrame *ref = find_ref_idx(s, poc, use_msb); if (ref == s->ref || list->nb_refs >= HEVC_MAX_REFS) return AVERROR_INVALIDDATA; @@ -485,7 +487,7 @@ int ff_hevc_frame_rps(HEVCContext *s) else list = ST_CURR_AFT; - ret = add_candidate_ref(s, &rps[list], poc, HEVC_FRAME_FLAG_SHORT_REF); + ret = add_candidate_ref(s, &rps[list], poc, HEVC_FRAME_FLAG_SHORT_REF, 1); if (ret < 0) goto fail; } @@ -495,7 +497,7 @@ int ff_hevc_frame_rps(HEVCContext *s) int poc = long_rps->poc[i]; int list = long_rps->used[i] ? LT_CURR : LT_FOLL; - ret = add_candidate_ref(s, &rps[list], poc, HEVC_FRAME_FLAG_LONG_REF); + ret = add_candidate_ref(s, &rps[list], poc, HEVC_FRAME_FLAG_LONG_REF, long_rps->poc_msb_present[i]); if (ret < 0) goto fail; }