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 67A064A1B0 for ; Sat, 23 Mar 2024 15:30:44 +0000 (UTC) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id E685F68D3D6; Sat, 23 Mar 2024 17:30:41 +0200 (EET) Received: from btbn.de (btbn.de [144.76.60.213]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id 8094D68D39B for ; Sat, 23 Mar 2024 17:30:35 +0200 (EET) Received: from [authenticated] by btbn.de (Postfix) with ESMTPSA id 7EC4928A8E33A; Sat, 23 Mar 2024 16:30:34 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rothenpieler.org; s=mail; t=1711207834; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=zDdNcmFMWXIXMrOtE7CmEzkFGb8yM59KJKVsU+/AlBw=; b=L+Hf2RclSsWI876thbpQAK1oJuizHWUt9cTG1aS5z737Oon2QYFbHSZt/nFyZ2dIP0LG4A y1Pmf5BAzmNoEnbvL8GUxxltLdW98hAUpC8PJXfJu8HYnBMgrBF2oax+CQx3zxwznVYG1k aaVV2vB8y9x9Ofj5r040RgUttt2WLzTqItKsteMuoCBFDb6Kz0u9I4vSx2OFcj++rzqwRu wULDeEOrI8/n91kcgMbQKXtVw7Dgl9eLO8ybpBsB1FSlAoq1I7ny/e5XfhXr2N/vUM6QUz cmxC0iDPw7Pnk8uE3+Y71osfPsOZVZOwGArNS3l4LmZ9vxFrKofeMyBm/7hzZg== From: Timo Rothenpieler To: ffmpeg-devel@ffmpeg.org Date: Sat, 23 Mar 2024 16:30:26 +0100 Message-Id: <20240323153026.1848-1-timo@rothenpieler.org> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 Subject: [FFmpeg-devel] [PATCH] avfilter/vf_stack: round down internal item heights 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 Cc: Timo Rothenpieler Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" Archived-At: List-Archive: List-Post: Following situation: Someone wants to stack two yuv420p frames of the size 3x3 pixel each. Now the various AV_CEIL_RSHIFT() calculations calculate a height of 2 pixel for each items subsampled planes. However, for example in case of a vstack, the output frames will have a height of 6, so the subsampled planes one of 3. When the filter now tries to stack two items with a rounded-up height of 2 into a frame with a height of 3, it'll write an entire extra line past the end of a buffer. This patch instead rounds down all the item heights, to avoid this situation. It's not ideal either, since now lines might be missed. But that is definitely preferable over writing past the end of the bufferThis patch instead rounds down all the item heights, to avoid this situation. It's not ideal either, since now lines might be missed. But that is definitely preferable over writing past the end of the buffer. --- libavfilter/vf_stack.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/libavfilter/vf_stack.c b/libavfilter/vf_stack.c index 2bb3d9b1d2..46e7d6b7f5 100644 --- a/libavfilter/vf_stack.c +++ b/libavfilter/vf_stack.c @@ -220,11 +220,11 @@ static int config_output(AVFilterLink *outlink) return ret; } - item->height[1] = item->height[2] = AV_CEIL_RSHIFT(inlink->h, s->desc->log2_chroma_h); + item->height[1] = item->height[2] = inlink->h / (1 << s->desc->log2_chroma_h); item->height[0] = item->height[3] = inlink->h; if (i) { - item->y[1] = item->y[2] = AV_CEIL_RSHIFT(height, s->desc->log2_chroma_h); + item->y[1] = item->y[2] = height / (1 << s->desc->log2_chroma_h); item->y[0] = item->y[3] = height; height += ctx->inputs[i]->h; @@ -244,7 +244,7 @@ static int config_output(AVFilterLink *outlink) return ret; } - item->height[1] = item->height[2] = AV_CEIL_RSHIFT(inlink->h, s->desc->log2_chroma_h); + item->height[1] = item->height[2] = inlink->h / (1 << s->desc->log2_chroma_h); item->height[0] = item->height[3] = inlink->h; if (i) { @@ -278,14 +278,14 @@ static int config_output(AVFilterLink *outlink) return ret; } - item->height[1] = item->height[2] = AV_CEIL_RSHIFT(inlink->h, s->desc->log2_chroma_h); + item->height[1] = item->height[2] = inlink->h / (1 << s->desc->log2_chroma_h); item->height[0] = item->height[3] = inlink->h; if ((ret = av_image_fill_linesizes(item->x, inlink->format, inw)) < 0) { return ret; } - item->y[1] = item->y[2] = AV_CEIL_RSHIFT(inh, s->desc->log2_chroma_h); + item->y[1] = item->y[2] = inh / (1 << s->desc->log2_chroma_h); item->y[0] = item->y[3] = inh; inw += ctx->inputs[k]->w; } @@ -322,7 +322,7 @@ static int config_output(AVFilterLink *outlink) return ret; } - item->height[1] = item->height[2] = AV_CEIL_RSHIFT(inlink->h, s->desc->log2_chroma_h); + item->height[1] = item->height[2] = inlink->h / (1 << s->desc->log2_chroma_h); item->height[0] = item->height[3] = inlink->h; p2 = arg; @@ -370,7 +370,7 @@ static int config_output(AVFilterLink *outlink) return ret; } - item->y[1] = item->y[2] = AV_CEIL_RSHIFT(inh, s->desc->log2_chroma_h); + item->y[1] = item->y[2] = inh / (1 << s->desc->log2_chroma_h); item->y[0] = item->y[3] = inh; width = FFMAX(width, inlink->w + inw); -- 2.34.1 _______________________________________________ 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".