From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ffbox0-bg.mplayerhq.hu (ffbox0-bg.ffmpeg.org [79.124.17.100]) by master.gitmailbox.com (Postfix) with ESMTP id 9376F493E8 for ; Fri, 9 Feb 2024 17:28:00 +0000 (UTC) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 8805868D048; Fri, 9 Feb 2024 19:27:57 +0200 (EET) Received: from w4.tutanota.de (w4.tutanota.de [81.3.6.165]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id 1493568AB9C for ; Fri, 9 Feb 2024 19:27:51 +0200 (EET) Received: from tutadb.w10.tutanota.de (unknown [192.168.1.10]) by w4.tutanota.de (Postfix) with ESMTP id AB2311060166 for ; Fri, 9 Feb 2024 17:27:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1707499670; s=s1; d=lynne.ee; h=From:From:To:To:Subject:Subject:Content-Description:Content-ID:Content-Type:Content-Type:Content-Transfer-Encoding:Cc:Date:Date:In-Reply-To:MIME-Version:MIME-Version:Message-ID:Message-ID:Reply-To:References:Sender; bh=xWmxYHX4bNnuGV68Wr2ylGYrUJRPVV1ZVf2fnyrKqes=; b=pW+w8INCSDtjiqwwH7WCEjB04MH7f+9B8ltWPWStuSUXpMYzjb4YG4QGSZbghYu7 lqHR5DfJ0ZtVGIQ4qktcxHznRkrgzyj6sXLF+8kaQi3GalbZFEGncOH2XEpjClm0nQ2 KHbrc77ltyCtsT7ndoaItcUu2wS1e5PLKsya8cSVvPildfZo5qoV3i/BHgbJsZLLrzR AUA34MG3oOnAfxy65v25e9GuBJFl+VPKdsJ+jgGUlMddxoa5mKQRkinC72gytwUeEAB itwpHLE1PoqFX4lhC7/cX1UttqXPVpf9U5FU1L4FpJ5JkwKdzWbD0KmTJV5IpjGYjEt PPniNBSPmQ== Date: Fri, 9 Feb 2024 18:27:50 +0100 (CET) From: Lynne To: Ffmpeg Devel Message-ID: MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="----=_Part_30744_525187509.1707499670276" Subject: [FFmpeg-devel] [PATCH] avfft: avoid overreads with RDFT API users 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" Archived-At: List-Archive: List-Post: ------=_Part_30744_525187509.1707499670276 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit The new API requires an extra array member at the very end, which old API users did not do. This disables in-place RDFT transforms and instead does the transform out of place by copying once, there shouldn't be a significant loss of speed as our in-place FFT requires a reorder which is likely more expensive in the majority of cases to do. Patch attached. ------=_Part_30744_525187509.1707499670276 Content-Type: text/x-diff; charset=us-ascii; name=0001-avfft-avoid-overreads-with-RDFT-API-users.patch Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename=0001-avfft-avoid-overreads-with-RDFT-API-users.patch >From 763f2e8941dc3dd4282ad42574bd8d451a256a53 Mon Sep 17 00:00:00 2001 From: Lynne Date: Fri, 9 Feb 2024 18:17:54 +0100 Subject: [PATCH] avfft: avoid overreads with RDFT API users The new API requires an extra array member at the very end, which old API users did not do. This disables in-place RDFT transforms and instead does the transform out of place by copying once, there shouldn't be a significant loss of speed as our in-place FFT requires a reorder which is likely more expensive in the majority of cases to do. --- libavcodec/avfft.c | 31 +++++++++++++++++++++++++------ 1 file changed, 25 insertions(+), 6 deletions(-) diff --git a/libavcodec/avfft.c b/libavcodec/avfft.c index 999b5ed79a..485f216427 100644 --- a/libavcodec/avfft.c +++ b/libavcodec/avfft.c @@ -152,7 +152,7 @@ RDFTContext *av_rdft_init(int nbits, enum RDFTransformType trans) return NULL; ret = av_tx_init(&s->ctx, &s->fn, AV_TX_FLOAT_RDFT, trans == IDFT_C2R, - 1 << nbits, &scale, AV_TX_INPLACE); + 1 << nbits, &scale, 0x0); if (ret < 0) { av_free(s); return NULL; @@ -162,17 +162,35 @@ RDFTContext *av_rdft_init(int nbits, enum RDFTransformType trans) s->len = 1 << nbits; s->inv = trans == IDFT_C2R; + s->tmp = av_malloc((s->len + 2)*sizeof(float)); + if (!s->tmp) { + av_tx_uninit(&s->ctx); + av_free(s); + return NULL; + } + return (RDFTContext *)s; } void av_rdft_calc(RDFTContext *s, FFTSample *data) { AVTXWrapper *w = (AVTXWrapper *)s; - if (w->inv) - FFSWAP(float, data[1], data[w->len]); - w->fn(w->ctx, data, (void *)data, w->stride); - if (!w->inv) - FFSWAP(float, data[1], data[w->len]); + float *src = w->inv ? w->tmp : (float *)data; + float *dst = w->inv ? (float *)data : w->tmp; + + if (w->inv) { + memcpy(src, data, w->len*sizeof(float)); + + src[w->len] = src[1]; + src[1] = 0.0f; + } + + w->fn(w->ctx, dst, (void *)src, w->stride); + + if (!w->inv) { + dst[1] = dst[w->len]; + memcpy(data, dst, w->len*sizeof(float)); + } } av_cold void av_rdft_end(RDFTContext *s) @@ -180,6 +198,7 @@ av_cold void av_rdft_end(RDFTContext *s) if (s) { AVTXWrapper *w = (AVTXWrapper *)s; av_tx_uninit(&w->ctx); + av_free(&w->tmp); av_free(w); } } -- 2.43.0.381.gb435a96ce8 ------=_Part_30744_525187509.1707499670276 Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe". ------=_Part_30744_525187509.1707499670276--