From 6a972dda58bd5ab31524cd4e5326b4bcdeaeaa8c Mon Sep 17 00:00:00 2001 From: rogerdpack Date: Wed, 23 Sep 2015 12:03:27 -0600 Subject: [PATCH] gdigrab: grab right desktop size if DPI in use, based on patch from Alexander Brotzge Signed-off-by: rogerdpack --- libavdevice/gdigrab.c | 44 +++++++++++++++++++++++++++++--------------- 1 file changed, 29 insertions(+), 15 deletions(-) diff --git a/libavdevice/gdigrab.c b/libavdevice/gdigrab.c index 9a185d4..b0faf45 100644 --- a/libavdevice/gdigrab.c +++ b/libavdevice/gdigrab.c @@ -235,6 +235,9 @@ gdigrab_read_header(AVFormatContext *s1) AVStream *st = NULL; int bpp; + int vertres; + int desktopvertres; + float scale; RECT virtual_rect; RECT clip_rect; BITMAP bmp; @@ -263,14 +266,34 @@ gdigrab_read_header(AVFormatContext *s1) goto error; } - if (hwnd) { - GetClientRect(hwnd, &virtual_rect); - } else { + /* This will get the device context for the selected window, or if + * none, the primary screen */ + source_hdc = GetDC(hwnd); + if (!source_hdc) { + WIN32_API_ERROR("Couldn't get window device context"); + ret = AVERROR(EIO); + goto error; + } + bpp = GetDeviceCaps(source_hdc, BITSPIXEL); + + scale = 1.0; + if (hwnd == NULL) { + /* desktop -- get the right height and width for scaling DPI */ + vertres = GetDeviceCaps(source_hdc, VERTRES); + desktopvertres = GetDeviceCaps(source_hdc, DESKTOPVERTRES); + scale = (float) desktopvertres / (float) vertres; + } + + if (hwnd) { + GetClientRect(hwnd, &virtual_rect); + virtual_rect.right = virtual_rect.right * scale; + virtual_rect.bottom = virtual_rect.bottom * scale; + } else { virtual_rect.left = GetSystemMetrics(SM_XVIRTUALSCREEN); virtual_rect.top = GetSystemMetrics(SM_YVIRTUALSCREEN); - virtual_rect.right = virtual_rect.left + GetSystemMetrics(SM_CXVIRTUALSCREEN); - virtual_rect.bottom = virtual_rect.top + GetSystemMetrics(SM_CYVIRTUALSCREEN); - } + virtual_rect.right = (virtual_rect.left + GetSystemMetrics(SM_CXVIRTUALSCREEN)) * scale; + virtual_rect.bottom = (virtual_rect.top + GetSystemMetrics(SM_CYVIRTUALSCREEN)) * scale; + } /* If no width or height set, use full screen/window area */ if (!gdigrab->width || !gdigrab->height) { @@ -299,15 +322,6 @@ gdigrab_read_header(AVFormatContext *s1) goto error; } - /* This will get the device context for the selected window, or if - * none, the primary screen */ - source_hdc = GetDC(hwnd); - if (!source_hdc) { - WIN32_API_ERROR("Couldn't get window device context"); - ret = AVERROR(EIO); - goto error; - } - bpp = GetDeviceCaps(source_hdc, BITSPIXEL); if (name) { av_log(s1, AV_LOG_INFO, -- 2.2.0