diff options
Diffstat (limited to 'libavdevice/gdigrab.c')
-rw-r--r-- | libavdevice/gdigrab.c | 649 |
1 files changed, 649 insertions, 0 deletions
diff --git a/libavdevice/gdigrab.c b/libavdevice/gdigrab.c new file mode 100644 index 0000000000..87f5012034 --- /dev/null +++ b/libavdevice/gdigrab.c @@ -0,0 +1,649 @@ +/* + * GDI video grab interface + * + * This file is part of FFmpeg. + * + * Copyright (C) 2013 Calvin Walton <calvin.walton@kepstin.ca> + * Copyright (C) 2007-2010 Christophe Gisquet <word1.word2@gmail.com> + * + * FFmpeg is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public License + * as published by the Free Software Foundation; either version 2.1 + * of the License, or (at your option) any later version. + * + * FFmpeg is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with FFmpeg; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +/** + * @file + * GDI frame device demuxer + * @author Calvin Walton <calvin.walton@kepstin.ca> + * @author Christophe Gisquet <word1.word2@gmail.com> + */ + +#include "config.h" +#include "libavformat/internal.h" +#include "libavutil/opt.h" +#include "libavutil/time.h" +#include <windows.h> + +/** + * GDI Device Demuxer context + */ +struct gdigrab { + const AVClass *class; /**< Class for private options */ + + int frame_size; /**< Size in bytes of the frame pixel data */ + int header_size; /**< Size in bytes of the DIB header */ + AVRational time_base; /**< Time base */ + int64_t time_frame; /**< Current time */ + + int draw_mouse; /**< Draw mouse cursor (private option) */ + int show_region; /**< Draw border (private option) */ + AVRational framerate; /**< Capture framerate (private option) */ + int width; /**< Width of the grab frame (private option) */ + int height; /**< Height of the grab frame (private option) */ + int offset_x; /**< Capture x offset (private option) */ + int offset_y; /**< Capture y offset (private option) */ + + HWND hwnd; /**< Handle of the window for the grab */ + HDC source_hdc; /**< Source device context */ + HDC dest_hdc; /**< Destination, source-compatible DC */ + BITMAPINFO bmi; /**< Information describing DIB format */ + HBITMAP hbmp; /**< Information on the bitmap captured */ + void *buffer; /**< The buffer containing the bitmap image data */ + RECT clip_rect; /**< The subarea of the screen or window to clip */ + + HWND region_hwnd; /**< Handle of the region border window */ + + int cursor_error_printed; +}; + +#define WIN32_API_ERROR(str) \ + av_log(s1, AV_LOG_ERROR, str " (error %li)\n", GetLastError()) + +#define REGION_WND_BORDER 3 + +/** + * Callback to handle Windows messages for the region outline window. + * + * In particular, this handles painting the frame rectangle. + * + * @param hwnd The region outline window handle. + * @param msg The Windows message. + * @param wparam First Windows message parameter. + * @param lparam Second Windows message parameter. + * @return 0 success, !0 failure + */ +static LRESULT CALLBACK +gdigrab_region_wnd_proc(HWND hwnd, UINT msg, WPARAM wparam, LPARAM lparam) +{ + PAINTSTRUCT ps; + HDC hdc; + RECT rect; + + switch (msg) { + case WM_PAINT: + hdc = BeginPaint(hwnd, &ps); + + GetClientRect(hwnd, &rect); + FrameRect(hdc, &rect, GetStockObject(BLACK_BRUSH)); + + rect.left++; rect.top++; rect.right--; rect.bottom--; + FrameRect(hdc, &rect, GetStockObject(WHITE_BRUSH)); + + rect.left++; rect.top++; rect.right--; rect.bottom--; + FrameRect(hdc, &rect, GetStockObject(BLACK_BRUSH)); + + EndPaint(hwnd, &ps); + break; + default: + return DefWindowProc(hwnd, msg, wparam, lparam); + } + return 0; +} + +/** + * Initialize the region outline window. + * + * @param s1 The format context. + * @param gdigrab gdigrab context. + * @return 0 success, !0 failure + */ +static int +gdigrab_region_wnd_init(AVFormatContext *s1, struct gdigrab *gdigrab) +{ + HWND hwnd; + RECT rect = gdigrab->clip_rect; + HRGN region = NULL; + HRGN region_interior = NULL; + + DWORD style = WS_POPUP | WS_VISIBLE; + DWORD ex = WS_EX_TOOLWINDOW | WS_EX_TOPMOST | WS_EX_TRANSPARENT; + + rect.left -= REGION_WND_BORDER; rect.top -= REGION_WND_BORDER; + rect.right += REGION_WND_BORDER; rect.bottom += REGION_WND_BORDER; + + AdjustWindowRectEx(&rect, style, FALSE, ex); + + // Create a window with no owner; use WC_DIALOG instead of writing a custom + // window class + hwnd = CreateWindowEx(ex, WC_DIALOG, NULL, style, rect.left, rect.top, + rect.right - rect.left, rect.bottom - rect.top, + NULL, NULL, NULL, NULL); + if (!hwnd) { + WIN32_API_ERROR("Could not create region display window"); + goto error; + } + + // Set the window shape to only include the border area + GetClientRect(hwnd, &rect); + region = CreateRectRgn(0, 0, + rect.right - rect.left, rect.bottom - rect.top); + region_interior = CreateRectRgn(REGION_WND_BORDER, REGION_WND_BORDER, + rect.right - rect.left - REGION_WND_BORDER, + rect.bottom - rect.top - REGION_WND_BORDER); + CombineRgn(region, region, region_interior, RGN_DIFF); + if (!SetWindowRgn(hwnd, region, FALSE)) { + WIN32_API_ERROR("Could not set window region"); + goto error; + } + // The "region" memory is now owned by the window + region = NULL; + DeleteObject(region_interior); + + SetWindowLongPtr(hwnd, GWLP_WNDPROC, (LONG_PTR) gdigrab_region_wnd_proc); + + ShowWindow(hwnd, SW_SHOW); + + gdigrab->region_hwnd = hwnd; + + return 0; + +error: + if (region) + DeleteObject(region); + if (region_interior) + DeleteObject(region_interior); + if (hwnd) + DestroyWindow(hwnd); + return 1; +} + +/** + * Cleanup/free the region outline window. + * + * @param s1 The format context. + * @param gdigrab gdigrab context. + */ +static void +gdigrab_region_wnd_destroy(AVFormatContext *s1, struct gdigrab *gdigrab) +{ + if (gdigrab->region_hwnd) + DestroyWindow(gdigrab->region_hwnd); + gdigrab->region_hwnd = NULL; +} + +/** + * Process the Windows message queue. + * + * This is important to prevent Windows from thinking the window has become + * unresponsive. As well, things like WM_PAINT (to actually draw the window + * contents) are handled from the message queue context. + * + * @param s1 The format context. + * @param gdigrab gdigrab context. + */ +static void +gdigrab_region_wnd_update(AVFormatContext *s1, struct gdigrab *gdigrab) +{ + HWND hwnd = gdigrab->region_hwnd; + MSG msg; + + while (PeekMessage(&msg, hwnd, 0, 0, PM_REMOVE)) { + DispatchMessage(&msg); + } +} + +/** + * Initializes the gdi grab device demuxer (public device demuxer API). + * + * @param s1 Context from avformat core + * @return AVERROR_IO error, 0 success + */ +static int +gdigrab_read_header(AVFormatContext *s1) +{ + struct gdigrab *gdigrab = s1->priv_data; + + HWND hwnd; + HDC source_hdc = NULL; + HDC dest_hdc = NULL; + BITMAPINFO bmi; + HBITMAP hbmp = NULL; + void *buffer = NULL; + + const char *filename = s1->filename; + const char *name = NULL; + AVStream *st = NULL; + + int bpp; + int vertres; + int desktopvertres; + RECT virtual_rect; + RECT clip_rect; + BITMAP bmp; + int ret; + + if (!strncmp(filename, "title=", 6)) { + name = filename + 6; + hwnd = FindWindow(NULL, name); + if (!hwnd) { + av_log(s1, AV_LOG_ERROR, + "Can't find window '%s', aborting.\n", name); + ret = AVERROR(EIO); + goto error; + } + if (gdigrab->show_region) { + av_log(s1, AV_LOG_WARNING, + "Can't show region when grabbing a window.\n"); + gdigrab->show_region = 0; + } + } else if (!strcmp(filename, "desktop")) { + hwnd = NULL; + } else { + av_log(s1, AV_LOG_ERROR, + "Please use \"desktop\" or \"title=<windowname>\" to specify your target.\n"); + ret = AVERROR(EIO); + 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 (hwnd) { + GetClientRect(hwnd, &virtual_rect); + } else { + /* desktop -- get the right height and width for scaling DPI */ + vertres = GetDeviceCaps(source_hdc, VERTRES); + desktopvertres = GetDeviceCaps(source_hdc, DESKTOPVERTRES); + virtual_rect.left = GetSystemMetrics(SM_XVIRTUALSCREEN); + virtual_rect.top = GetSystemMetrics(SM_YVIRTUALSCREEN); + virtual_rect.right = (virtual_rect.left + GetSystemMetrics(SM_CXVIRTUALSCREEN)) * desktopvertres / vertres; + virtual_rect.bottom = (virtual_rect.top + GetSystemMetrics(SM_CYVIRTUALSCREEN)) * desktopvertres / vertres; + } + + /* If no width or height set, use full screen/window area */ + if (!gdigrab->width || !gdigrab->height) { + clip_rect.left = virtual_rect.left; + clip_rect.top = virtual_rect.top; + clip_rect.right = virtual_rect.right; + clip_rect.bottom = virtual_rect.bottom; + } else { + clip_rect.left = gdigrab->offset_x; + clip_rect.top = gdigrab->offset_y; + clip_rect.right = gdigrab->width + gdigrab->offset_x; + clip_rect.bottom = gdigrab->height + gdigrab->offset_y; + } + + if (clip_rect.left < virtual_rect.left || + clip_rect.top < virtual_rect.top || + clip_rect.right > virtual_rect.right || + clip_rect.bottom > virtual_rect.bottom) { + av_log(s1, AV_LOG_ERROR, + "Capture area (%li,%li),(%li,%li) extends outside window area (%li,%li),(%li,%li)", + clip_rect.left, clip_rect.top, + clip_rect.right, clip_rect.bottom, + virtual_rect.left, virtual_rect.top, + virtual_rect.right, virtual_rect.bottom); + ret = AVERROR(EIO); + goto error; + } + + + if (name) { + av_log(s1, AV_LOG_INFO, + "Found window %s, capturing %lix%lix%i at (%li,%li)\n", + name, + clip_rect.right - clip_rect.left, + clip_rect.bottom - clip_rect.top, + bpp, clip_rect.left, clip_rect.top); + } else { + av_log(s1, AV_LOG_INFO, + "Capturing whole desktop as %lix%lix%i at (%li,%li)\n", + clip_rect.right - clip_rect.left, + clip_rect.bottom - clip_rect.top, + bpp, clip_rect.left, clip_rect.top); + } + + if (clip_rect.right - clip_rect.left <= 0 || + clip_rect.bottom - clip_rect.top <= 0 || bpp%8) { + av_log(s1, AV_LOG_ERROR, "Invalid properties, aborting\n"); + ret = AVERROR(EIO); + goto error; + } + + dest_hdc = CreateCompatibleDC(source_hdc); + if (!dest_hdc) { + WIN32_API_ERROR("Screen DC CreateCompatibleDC"); + ret = AVERROR(EIO); + goto error; + } + + /* Create a DIB and select it into the dest_hdc */ + bmi.bmiHeader.biSize = sizeof(BITMAPINFOHEADER); + bmi.bmiHeader.biWidth = clip_rect.right - clip_rect.left; + bmi.bmiHeader.biHeight = -(clip_rect.bottom - clip_rect.top); + bmi.bmiHeader.biPlanes = 1; + bmi.bmiHeader.biBitCount = bpp; + bmi.bmiHeader.biCompression = BI_RGB; + bmi.bmiHeader.biSizeImage = 0; + bmi.bmiHeader.biXPelsPerMeter = 0; + bmi.bmiHeader.biYPelsPerMeter = 0; + bmi.bmiHeader.biClrUsed = 0; + bmi.bmiHeader.biClrImportant = 0; + hbmp = CreateDIBSection(dest_hdc, &bmi, DIB_RGB_COLORS, + &buffer, NULL, 0); + if (!hbmp) { + WIN32_API_ERROR("Creating DIB Section"); + ret = AVERROR(EIO); + goto error; + } + + if (!SelectObject(dest_hdc, hbmp)) { + WIN32_API_ERROR("SelectObject"); + ret = AVERROR(EIO); + goto error; + } + + /* Get info from the bitmap */ + GetObject(hbmp, sizeof(BITMAP), &bmp); + + st = avformat_new_stream(s1, NULL); + if (!st) { + ret = AVERROR(ENOMEM); + goto error; + } + avpriv_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */ + + gdigrab->frame_size = bmp.bmWidthBytes * bmp.bmHeight * bmp.bmPlanes; + gdigrab->header_size = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER) + + (bpp <= 8 ? (1 << bpp) : 0) * sizeof(RGBQUAD) /* palette size */; + gdigrab->time_base = av_inv_q(gdigrab->framerate); + gdigrab->time_frame = av_gettime() / av_q2d(gdigrab->time_base); + + gdigrab->hwnd = hwnd; + gdigrab->source_hdc = source_hdc; + gdigrab->dest_hdc = dest_hdc; + gdigrab->hbmp = hbmp; + gdigrab->bmi = bmi; + gdigrab->buffer = buffer; + gdigrab->clip_rect = clip_rect; + + gdigrab->cursor_error_printed = 0; + + if (gdigrab->show_region) { + if (gdigrab_region_wnd_init(s1, gdigrab)) { + ret = AVERROR(EIO); + goto error; + } + } + + st->avg_frame_rate = av_inv_q(gdigrab->time_base); + + st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO; + st->codecpar->codec_id = AV_CODEC_ID_BMP; + st->codecpar->bit_rate = (gdigrab->header_size + gdigrab->frame_size) * 1/av_q2d(gdigrab->time_base) * 8; + + return 0; + +error: + if (source_hdc) + ReleaseDC(hwnd, source_hdc); + if (dest_hdc) + DeleteDC(dest_hdc); + if (hbmp) + DeleteObject(hbmp); + if (source_hdc) + DeleteDC(source_hdc); + return ret; +} + +/** + * Paints a mouse pointer in a Win32 image. + * + * @param s1 Context of the log information + * @param s Current grad structure + */ +static void paint_mouse_pointer(AVFormatContext *s1, struct gdigrab *gdigrab) +{ + CURSORINFO ci = {0}; + +#define CURSOR_ERROR(str) \ + if (!gdigrab->cursor_error_printed) { \ + WIN32_API_ERROR(str); \ + gdigrab->cursor_error_printed = 1; \ + } + + ci.cbSize = sizeof(ci); + + if (GetCursorInfo(&ci)) { + HCURSOR icon = CopyCursor(ci.hCursor); + ICONINFO info; + POINT pos; + RECT clip_rect = gdigrab->clip_rect; + HWND hwnd = gdigrab->hwnd; + int vertres = GetDeviceCaps(gdigrab->source_hdc, VERTRES); + int desktopvertres = GetDeviceCaps(gdigrab->source_hdc, DESKTOPVERTRES); + info.hbmMask = NULL; + info.hbmColor = NULL; + + if (ci.flags != CURSOR_SHOWING) + return; + + if (!icon) { + /* Use the standard arrow cursor as a fallback. + * You'll probably only hit this in Wine, which can't fetch + * the current system cursor. */ + icon = CopyCursor(LoadCursor(NULL, IDC_ARROW)); + } + + if (!GetIconInfo(icon, &info)) { + CURSOR_ERROR("Could not get icon info"); + goto icon_error; + } + + pos.x = ci.ptScreenPos.x - clip_rect.left - info.xHotspot; + pos.y = ci.ptScreenPos.y - clip_rect.top - info.yHotspot; + + if (hwnd) { + RECT rect; + + if (GetWindowRect(hwnd, &rect)) { + pos.x -= rect.left; + pos.y -= rect.top; + } else { + CURSOR_ERROR("Couldn't get window rectangle"); + goto icon_error; + } + } + + //that would keep the correct location of mouse with hidpi screens + pos.x = pos.x * desktopvertres / vertres; + pos.y = pos.y * desktopvertres / vertres; + + av_log(s1, AV_LOG_DEBUG, "Cursor pos (%li,%li) -> (%li,%li)\n", + ci.ptScreenPos.x, ci.ptScreenPos.y, pos.x, pos.y); + + if (pos.x >= 0 && pos.x <= clip_rect.right - clip_rect.left && + pos.y >= 0 && pos.y <= clip_rect.bottom - clip_rect.top) { + if (!DrawIcon(gdigrab->dest_hdc, pos.x, pos.y, icon)) + CURSOR_ERROR("Couldn't draw icon"); + } + +icon_error: + if (info.hbmMask) + DeleteObject(info.hbmMask); + if (info.hbmColor) + DeleteObject(info.hbmColor); + if (icon) + DestroyCursor(icon); + } else { + CURSOR_ERROR("Couldn't get cursor info"); + } +} + +/** + * Grabs a frame from gdi (public device demuxer API). + * + * @param s1 Context from avformat core + * @param pkt Packet holding the grabbed frame + * @return frame size in bytes + */ +static int gdigrab_read_packet(AVFormatContext *s1, AVPacket *pkt) +{ + struct gdigrab *gdigrab = s1->priv_data; + + HDC dest_hdc = gdigrab->dest_hdc; + HDC source_hdc = gdigrab->source_hdc; + RECT clip_rect = gdigrab->clip_rect; + AVRational time_base = gdigrab->time_base; + int64_t time_frame = gdigrab->time_frame; + + BITMAPFILEHEADER bfh; + int file_size = gdigrab->header_size + gdigrab->frame_size; + + int64_t curtime, delay; + + /* Calculate the time of the next frame */ + time_frame += INT64_C(1000000); + + /* Run Window message processing queue */ + if (gdigrab->show_region) + gdigrab_region_wnd_update(s1, gdigrab); + + /* wait based on the frame rate */ + for (;;) { + curtime = av_gettime(); + delay = time_frame * av_q2d(time_base) - curtime; + if (delay <= 0) { + if (delay < INT64_C(-1000000) * av_q2d(time_base)) { + time_frame += INT64_C(1000000); + } + break; + } + if (s1->flags & AVFMT_FLAG_NONBLOCK) { + return AVERROR(EAGAIN); + } else { + av_usleep(delay); + } + } + + if (av_new_packet(pkt, file_size) < 0) + return AVERROR(ENOMEM); + pkt->pts = curtime; + + /* Blit screen grab */ + if (!BitBlt(dest_hdc, 0, 0, + clip_rect.right - clip_rect.left, + clip_rect.bottom - clip_rect.top, + source_hdc, + clip_rect.left, clip_rect.top, SRCCOPY | CAPTUREBLT)) { + WIN32_API_ERROR("Failed to capture image"); + return AVERROR(EIO); + } + if (gdigrab->draw_mouse) + paint_mouse_pointer(s1, gdigrab); + + /* Copy bits to packet data */ + + bfh.bfType = 0x4d42; /* "BM" in little-endian */ + bfh.bfSize = file_size; + bfh.bfReserved1 = 0; + bfh.bfReserved2 = 0; + bfh.bfOffBits = gdigrab->header_size; + + memcpy(pkt->data, &bfh, sizeof(bfh)); + + memcpy(pkt->data + sizeof(bfh), &gdigrab->bmi.bmiHeader, sizeof(gdigrab->bmi.bmiHeader)); + + if (gdigrab->bmi.bmiHeader.biBitCount <= 8) + GetDIBColorTable(dest_hdc, 0, 1 << gdigrab->bmi.bmiHeader.biBitCount, + (RGBQUAD *) (pkt->data + sizeof(bfh) + sizeof(gdigrab->bmi.bmiHeader))); + + memcpy(pkt->data + gdigrab->header_size, gdigrab->buffer, gdigrab->frame_size); + + gdigrab->time_frame = time_frame; + + return gdigrab->header_size + gdigrab->frame_size; +} + +/** + * Closes gdi frame grabber (public device demuxer API). + * + * @param s1 Context from avformat core + * @return 0 success, !0 failure + */ +static int gdigrab_read_close(AVFormatContext *s1) +{ + struct gdigrab *s = s1->priv_data; + + if (s->show_region) + gdigrab_region_wnd_destroy(s1, s); + + if (s->source_hdc) + ReleaseDC(s->hwnd, s->source_hdc); + if (s->dest_hdc) + DeleteDC(s->dest_hdc); + if (s->hbmp) + DeleteObject(s->hbmp); + if (s->source_hdc) + DeleteDC(s->source_hdc); + + return 0; +} + +#define OFFSET(x) offsetof(struct gdigrab, x) +#define DEC AV_OPT_FLAG_DECODING_PARAM +static const AVOption options[] = { + { "draw_mouse", "draw the mouse pointer", OFFSET(draw_mouse), AV_OPT_TYPE_INT, {.i64 = 1}, 0, 1, DEC }, + { "show_region", "draw border around capture area", OFFSET(show_region), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 1, DEC }, + { "framerate", "set video frame rate", OFFSET(framerate), AV_OPT_TYPE_VIDEO_RATE, {.str = "ntsc"}, 0, INT_MAX, DEC }, + { "video_size", "set video frame size", OFFSET(width), AV_OPT_TYPE_IMAGE_SIZE, {.str = NULL}, 0, 0, DEC }, + { "offset_x", "capture area x offset", OFFSET(offset_x), AV_OPT_TYPE_INT, {.i64 = 0}, INT_MIN, INT_MAX, DEC }, + { "offset_y", "capture area y offset", OFFSET(offset_y), AV_OPT_TYPE_INT, {.i64 = 0}, INT_MIN, INT_MAX, DEC }, + { NULL }, +}; + +static const AVClass gdigrab_class = { + .class_name = "GDIgrab indev", + .item_name = av_default_item_name, + .option = options, + .version = LIBAVUTIL_VERSION_INT, +}; + +/** gdi grabber device demuxer declaration */ +AVInputFormat ff_gdigrab_demuxer = { + .name = "gdigrab", + .long_name = NULL_IF_CONFIG_SMALL("GDI API Windows frame grabber"), + .priv_data_size = sizeof(struct gdigrab), + .read_header = gdigrab_read_header, + .read_packet = gdigrab_read_packet, + .read_close = gdigrab_read_close, + .flags = AVFMT_NOFILE, + .priv_class = &gdigrab_class, +}; |