]> git.decadent.org.uk Git - videolink.git/blobdiff - webdvd.cpp
Added support for mjpegtools 1.8 (now the default) and experimental support for ffmpe...
[videolink.git] / webdvd.cpp
index 5b3cd9b998b65375f1139d58ad9fa0e1d92f269a..5fd5e6ff8774a34bbb70345a2c8d32e5af05da3b 100644 (file)
@@ -1,4 +1,4 @@
-// Copyright 2005 Ben Hutchings <ben@decadentplace.org.uk>.
+// Copyright 2005-6 Ben Hutchings <ben@decadentplace.org.uk>.
 // See the file "COPYING" for licence details.
 
 #include <cassert>
 #include <nsIInterfaceRequestorUtils.h>
 #include <nsIURI.h> // required before nsILink.h
 #include <nsILink.h>
+#include <nsIPrefBranch.h>
+#include <nsIPrefService.h>
 #include <nsIPresContext.h>
 #include <nsIPresShell.h>
+#include <nsIServiceManagerUtils.h>
 #include <nsIWebBrowser.h>
 #include <nsString.h>
 
-#include "browserwidget.hpp"
-#include "childiterator.hpp"
+#include "browser_widget.hpp"
+#include "child_iterator.hpp"
 #include "dvd.hpp"
-#include "framebuffer.hpp"
-#include "linkiterator.hpp"
+#include "generate_dvd.hpp"
+#include "link_iterator.hpp"
+#include "null_prompt_service.hpp"
 #include "pixbufs.hpp"
-#include "stylesheets.hpp"
+#include "style_sheets.hpp"
 #include "temp_file.hpp"
 #include "video.hpp"
+#include "x_frame_buffer.hpp"
+#include "xml_utils.hpp"
 #include "xpcom_support.hpp"
 
 using xpcom_support::check;
 
 namespace
 {
+    // We can try using any of these encoders to convert PNG to MPEG.
+    enum mpeg_encoder
+    {
+       mpeg_encoder_ffmpeg,         // ffmpeg - doesn't work yet
+       mpeg_encoder_mjpegtools_old, // mjpegtools before version 1.8
+       mpeg_encoder_mjpegtools_new  // mjpegtools from version 1.8
+    };
+
     struct rectangle
     {
        int left, top;     // inclusive
@@ -123,7 +137,7 @@ namespace
        result.bottom = result.top + height;
 
        // Merge bounding boxes of all child elements
-       for (ChildIterator it = ChildIterator(elem), end; it != end; ++it)
+       for (child_iterator it = child_iterator(elem), end; it != end; ++it)
        {
            nsCOMPtr<nsIDOMNode> child_node(*it);
            PRUint16 child_type;
@@ -139,55 +153,67 @@ namespace
        return result;
     }
 
-    class WebDvdWindow : public Gtk::Window
+
+    class webdvd_window : public Gtk::Window
     {
     public:
-       WebDvdWindow(
+       webdvd_window(
            const video::frame_params & frame_params,
            const std::string & main_page_uri,
-           const std::string & output_dir);
+           const std::string & output_dir,
+           mpeg_encoder encoder);
+
+       bool is_finished() const;
 
     private:
-       void add_page(const std::string & uri);
-       void add_video(const std::string & uri);
+       dvd_contents::pgc_ref add_menu(const std::string & uri);
+       dvd_contents::pgc_ref add_title(const std::string & uri);
        void load_next_page();
        void on_net_state_change(const char * uri, gint flags, guint status);
+       bool browser_is_busy() const
+           {
+               return pending_window_update_ || pending_req_count_;
+           }
        bool process_page();
        void save_screenshot();
        void process_links(nsIPresShell * pres_shell,
                           nsIPresContext * pres_context,
                           nsIDOMWindow * dom_window);
-       void generate_dvd();
 
-       enum ResourceType { page_resource, video_resource };
-       typedef std::pair<ResourceType, int> ResourceEntry;
        video::frame_params frame_params_;
        std::string output_dir_;
-       BrowserWidget browser_widget_;
+       mpeg_encoder encoder_;
+       browser_widget browser_widget_;
        nsCOMPtr<nsIStyleSheet> stylesheet_;
+
+       dvd_contents contents_;
+       typedef std::map<std::string, dvd_contents::pgc_ref> resource_map_type;
+       resource_map_type resource_map_;
+
        std::queue<std::string> page_queue_;
-       std::map<std::string, ResourceEntry> resource_map_;
-       std::vector<std::vector<std::string> > page_links_;
-       std::vector<std::string> video_paths_;
        bool pending_window_update_;
        int pending_req_count_;
        bool have_tweaked_page_;
        std::auto_ptr<temp_file> background_temp_;
        struct page_state;
        std::auto_ptr<page_state> page_state_;
-       std::vector<boost::shared_ptr<temp_file> > page_temp_files_;
+
+       bool finished_;
     };
 
-    WebDvdWindow::WebDvdWindow(
+    webdvd_window::webdvd_window(
        const video::frame_params & frame_params,
        const std::string & main_page_uri,
-       const std::string & output_dir)
+       const std::string & output_dir,
+       mpeg_encoder encoder)
            : frame_params_(frame_params),
              output_dir_(output_dir),
+             encoder_(encoder),
              stylesheet_(load_css("file://" WEBDVD_LIB_DIR "/webdvd.css")),
              pending_window_update_(false),
              pending_req_count_(0),
-             have_tweaked_page_(false)
+             have_tweaked_page_(false),
+             finished_(false)
     {
        set_size_request(frame_params_.width, frame_params_.height);
        set_resizable(false);
@@ -195,51 +221,129 @@ namespace
        add(browser_widget_);
        browser_widget_.show();
        browser_widget_.signal_net_state().connect(
-           SigC::slot(*this, &WebDvdWindow::on_net_state_change));
+           SigC::slot(*this, &webdvd_window::on_net_state_change));
 
-       add_page(main_page_uri);
+       add_menu(main_page_uri);
        load_next_page();
     }
 
-    void WebDvdWindow::add_page(const std::string & uri)
+    bool webdvd_window::is_finished() const
     {
-       if (resource_map_.insert(
-               std::make_pair(uri, ResourceEntry(page_resource, 0)))
-           .second)
+       return finished_;
+    }
+
+    dvd_contents::pgc_ref webdvd_window::add_menu(const std::string & uri)
+    {
+       dvd_contents::pgc_ref next_menu(dvd_contents::menu_pgc,
+                                       contents_.menus.size());
+       std::pair<resource_map_type::iterator, bool> insert_result(
+           resource_map_.insert(std::make_pair(uri, next_menu)));
+
+       if (!insert_result.second)
+       {
+           return insert_result.first->second;
+       }
+       else
        {
            page_queue_.push(uri);
+           contents_.menus.resize(contents_.menus.size() + 1);
+           return next_menu;
        }
     }
 
-    void WebDvdWindow::add_video(const std::string & uri)
+    dvd_contents::pgc_ref webdvd_window::add_title(const std::string & uri)
     {
-       if (resource_map_.insert(
-               std::make_pair(uri, ResourceEntry(video_resource,
-                                                 video_paths_.size() + 1)))
-           .second)
+       dvd_contents::pgc_ref next_title(dvd_contents::title_pgc,
+                                        contents_.titles.size());
+       std::pair<resource_map_type::iterator, bool> insert_result(
+           resource_map_.insert(std::make_pair(uri, next_title)));
+
+       if (!insert_result.second)
+       {
+           return insert_result.first->second;
+       }
+       else
        {
            Glib::ustring hostname;
-           video_paths_.push_back(Glib::filename_from_uri(uri, hostname));
+           std::string path(Glib::filename_from_uri(uri, hostname));
            // FIXME: Should check the hostname
+
+           vob_list list;
+
+           // Store a reference to a linked VOB file, or the contents
+           // of a linked VOB list file.
+           if (path.compare(path.size() - 4, 4, ".vob") == 0)
+           {
+               if (!Glib::file_test(path, Glib::FILE_TEST_IS_REGULAR))
+                   throw std::runtime_error(
+                       path + " is missing or not a regular file");
+               vob_ref ref;
+               ref.file = path;
+               list.push_back(ref);
+           }
+           else
+           {
+               assert(path.compare(path.size() - 8, 8, ".voblist") == 0);
+               read_vob_list(path).swap(list);
+           }
+
+           contents_.titles.resize(contents_.titles.size() + 1);
+           contents_.titles.back().swap(list);
+           return next_title;
        }
     }
 
-    void WebDvdWindow::load_next_page()
+    void webdvd_window::load_next_page()
     {
        assert(!page_queue_.empty());
        const std::string & uri = page_queue_.front();
        std::cout << "loading " << uri << std::endl;
 
-       std::size_t page_count = page_links_.size();
-       resource_map_[uri].second = ++page_count;
-       page_links_.resize(page_count);
-
        browser_widget_.load_uri(uri);
     }
 
-    void WebDvdWindow::on_net_state_change(const char * uri,
+    void webdvd_window::on_net_state_change(const char * uri,
                                           gint flags, guint status)
     {
+#       ifdef DEBUG_ON_NET_STATE_CHANGE
+       std::cout << "webdvd_window::on_net_state_change(";
+       if (uri)
+           std::cout << '"' << uri << '"';
+       else
+           std::cout << "NULL";
+       std::cout << ", ";
+       {
+           gint flags_left = flags;
+           static const struct {
+               gint value;
+               const char * name;
+           } flag_names[] = {
+               { GTK_MOZ_EMBED_FLAG_START, "STATE_START" },
+               { GTK_MOZ_EMBED_FLAG_REDIRECTING, "STATE_REDIRECTING" },
+               { GTK_MOZ_EMBED_FLAG_TRANSFERRING, "STATE_TRANSFERRING" },
+               { GTK_MOZ_EMBED_FLAG_NEGOTIATING, "STATE_NEGOTIATING" },
+               { GTK_MOZ_EMBED_FLAG_STOP, "STATE_STOP" },
+               { GTK_MOZ_EMBED_FLAG_IS_REQUEST, "STATE_IS_REQUEST" },
+               { GTK_MOZ_EMBED_FLAG_IS_DOCUMENT, "STATE_IS_DOCUMENT" },
+               { GTK_MOZ_EMBED_FLAG_IS_NETWORK, "STATE_IS_NETWORK" },
+               { GTK_MOZ_EMBED_FLAG_IS_WINDOW, "STATE_IS_WINDOW" }
+           };
+           for (int i = 0; i != sizeof(flag_names)/sizeof(flag_names[0]); ++i)
+           {
+               if (flags & flag_names[i].value)
+               {
+                   std::cout << flag_names[i].name;
+                   flags_left -= flag_names[i].value;
+                   if (flags_left)
+                       std::cout << " | ";
+               }
+           }
+           if (flags_left)
+               std::cout << "0x" << std::setbase(16) << flags_left;
+       }
+       std::cout << ", " << "0x" << std::setbase(16) << status << ")\n";
+#       endif // DEBUG_ON_NET_STATE_CHANGE
+
        if (flags & GTK_MOZ_EMBED_FLAG_IS_REQUEST)
        {
            if (flags & GTK_MOZ_EMBED_FLAG_START)
@@ -270,12 +374,15 @@ namespace
            pending_window_update_ = false;
        }
 
-       if (pending_req_count_ == 0 && !pending_window_update_)
+       if (!browser_is_busy())
        {
            try
            {
                if (!process_page())
+               {
+                   finished_ = true;
                    Gtk::Main::quit();
+               }
            }
            catch (std::exception & e)
            {
@@ -286,10 +393,19 @@ namespace
                std::cerr << ": " << e.what() << "\n";
                Gtk::Main::quit();
            }
+           catch (Glib::Exception & e)
+           {
+               std::cerr << "Fatal error";
+               if (!page_queue_.empty())
+                   std::cerr << " while processing <" << page_queue_.front()
+                             << ">";
+               std::cerr << ": " << e.what() << "\n";
+               Gtk::Main::quit();
+           }
        }
     }
 
-    bool WebDvdWindow::process_page()
+    bool webdvd_window::process_page()
     {
        assert(!page_queue_.empty());
 
@@ -318,14 +434,14 @@ namespace
 
            // Might need to wait a while for things to load or more
            // likely for a re-layout.
-           if (pending_req_count_ > 0)
+           if (browser_is_busy())
                return true;
        }
 
        // All further work should only be done if we're not in preview mode.
        if (!output_dir_.empty())
        {
-           // If we haven't already started work on this page, save a
+           // If we haven't already started work on this menu, save a
            // screenshot of its normal appearance.
            if (!page_state_.get())
                save_screenshot();
@@ -340,7 +456,7 @@ namespace
                page_queue_.pop();
                if (page_queue_.empty())
                {
-                   generate_dvd();
+                   generate_dvd(contents_, output_dir_);
                    return false;
                }
                else
@@ -353,7 +469,7 @@ namespace
        return true;
     }
 
-    void WebDvdWindow::save_screenshot()
+    void webdvd_window::save_screenshot()
     {
        Glib::RefPtr<Gdk::Window> window(get_window());
        assert(window);
@@ -369,7 +485,7 @@ namespace
            ->save(background_temp_->get_name(), "png");
     }
 
-    struct WebDvdWindow::page_state
+    struct webdvd_window::page_state
     {
        page_state(nsIDOMDocument * doc, int width, int height)
                : diff_pixbuf(Gdk::Pixbuf::create(
@@ -393,15 +509,15 @@ namespace
 
        temp_file links_temp;
 
-       int link_num;
-       LinkIterator links_it, links_end;
+       unsigned link_num;
+       link_iterator links_it, links_end;
 
        rectangle link_rect;
        bool link_changing;
        Glib::RefPtr<Gdk::Pixbuf> norm_pixbuf;
     };
 
-    void WebDvdWindow::process_links(nsIPresShell * pres_shell,
+    void webdvd_window::process_links(nsIPresShell * pres_shell,
                                     nsIPresContext * pres_context,
                                     nsIDOMWindow * dom_window)
     {
@@ -444,25 +560,32 @@ namespace
            0, 0, frame_params_.width, frame_params_.height
        };
 
+       unsigned menu_num = resource_map_[page_queue_.front()].index;
+
        for (/* no initialisation */;
             state->links_it != state->links_end;
             ++state->links_it)
        {
            nsCOMPtr<nsIDOMNode> node(*state->links_it);
 
-           // Find the link URI.
+           // Find the link URI and separate any fragment from it.
            nsCOMPtr<nsILink> link(do_QueryInterface(node));
            assert(link);
-           nsCOMPtr<nsIURI> uri;
-           check(link->GetHrefURI(getter_AddRefs(uri)));
-           std::string uri_string;
+           nsCOMPtr<nsIURI> uri_iface;
+           check(link->GetHrefURI(getter_AddRefs(uri_iface)));
+           std::string uri_and_fragment, uri, fragment;
            {
-               nsCString uri_ns_string;
-               check(uri->GetSpec(uri_ns_string));
-               uri_string.assign(uri_ns_string.BeginReading(),
-                                 uri_ns_string.EndReading());
+               nsCString uri_and_fragment_ns;
+               check(uri_iface->GetSpec(uri_and_fragment_ns));
+               uri_and_fragment.assign(uri_and_fragment_ns.BeginReading(),
+                                       uri_and_fragment_ns.EndReading());
+
+               std::size_t hash_pos = uri_and_fragment.find('#');
+               uri.assign(uri_and_fragment, 0, hash_pos);
+               if (hash_pos != std::string::npos)
+                   fragment.assign(uri_and_fragment,
+                                   hash_pos + 1, std::string::npos);
            }
-           std::string uri_sans_fragment(uri_string, 0, uri_string.find('#'));
 
            // Is this a new link?
            if (!state->link_changing)
@@ -477,44 +600,58 @@ namespace
                if (state->link_rect.empty())
                {
                    std::cerr << "Ignoring invisible link to "
-                             << uri_string << "\n";
+                             << uri_and_fragment << "\n";
                    continue;
                }
 
                ++state->link_num;
 
-               if (state->link_num >= dvd::menu_buttons_max)
+               if (state->link_num >= unsigned(dvd::menu_buttons_max))
                {
-                   if (state->link_num == dvd::menu_buttons_max)
+                   if (state->link_num == unsigned(dvd::menu_buttons_max))
                        std::cerr << "No more than " << dvd::menu_buttons_max
-                                 << " buttons can be placed on a page\n";
-                   std::cerr << "Ignoring link to " << uri_string << "\n";
+                                 << " buttons can be placed on a menu\n";
+                   std::cerr << "Ignoring link to " << uri_and_fragment
+                             << "\n";
                    continue;
                }
 
+               state->spumux_file <<
+                   "      <button x0='" << state->link_rect.left << "'"
+                   " y0='" << state->link_rect.top << "'"
+                   " x1='" << state->link_rect.right - 1 << "'"
+                   " y1='" << state->link_rect.bottom - 1 << "'/>\n";
+
                // Check whether this is a link to a video or a page then
-               // add it to the known resources if not already seen.
-               nsCString path;
-               check(uri->GetPath(path));
+               // add it to the known resources if not already seen; then
+               // add it to the menu entries.
+               dvd_contents::pgc_ref target;
                // FIXME: This is a bit of a hack.  Perhaps we could decide
                // later based on the MIME type determined by Mozilla?
-               if (path.Length() > 4
-                   && std::strcmp(path.EndReading() - 4, ".vob") == 0)
+               if ((uri.size() > 4
+                    && uri.compare(uri.size() - 4, 4, ".vob") == 0)
+                   || (uri.size() > 8
+                       && uri.compare(uri.size() - 8, 8, ".voblist") == 0))
                {
                    PRBool is_file;
-                   check(uri->SchemeIs("file", &is_file));
+                   check(uri_iface->SchemeIs("file", &is_file));
                    if (!is_file)
                    {
                        std::cerr << "Links to video must use the file:"
                                  << " scheme\n";
                        continue;
                    }
-                   add_video(uri_sans_fragment);
+                   target = add_title(uri);
+                   target.sub_index =
+                       std::strtoul(fragment.c_str(), NULL, 10);
                }
                else
                {
-                   add_page(uri_sans_fragment);
+                   target = add_menu(uri);
+                   // TODO: If there's a fragment, work out which button
+                   // is closest and set target.sub_index.
                }
+               contents_.menus[menu_num].entries.push_back(target);
 
                nsCOMPtr<nsIContent> content(do_QueryInterface(node));
                assert(content);
@@ -563,7 +700,7 @@ namespace
                // We may have to exit and wait for image loading
                // to complete, at which point we will be called
                // again.
-               if (pending_req_count_ > 0)
+               if (browser_is_busy())
                {
                    state->link_changing = true;
                    page_state_ = state;
@@ -591,15 +728,6 @@ namespace
                state->link_rect.top,
                state->link_rect.right - state->link_rect.left,
                state->link_rect.bottom - state->link_rect.top);
-
-           state->spumux_file <<
-               "      <button x0='" << state->link_rect.left << "'"
-               " y0='" << state->link_rect.top << "'"
-               " x1='" << state->link_rect.right - 1 << "'"
-               " y1='" << state->link_rect.bottom - 1 << "'/>\n";
-
-           // Add to the page's links, ignoring any fragment (for now).
-           page_links_.back().push_back(uri_sans_fragment);
        }
 
        quantise_rgba_pixbuf(state->diff_pixbuf, dvd::button_n_colours);
@@ -618,22 +746,46 @@ namespace
        // TODO: if (!state->spumux_file) throw ...
 
        {
-           boost::shared_ptr<temp_file> vob_temp(
-               new temp_file("webdvd-vob-"));
            std::ostringstream command_stream;
-           command_stream << "pngtopnm "
-                          << background_temp_->get_name()
-                          << " | ppmtoy4m -v0 -n1 -F"
-                          << frame_params_.rate_numer
-                          << ":" << frame_params_.rate_denom
-                          << " -A" << frame_params_.pixel_ratio_width
-                          << ":" << frame_params_.pixel_ratio_height
-                          << (" -Ip -S420_mpeg2"
-                              " | mpeg2enc -v0 -f8 -a2 -o/dev/stdout"
-                              " | mplex -v0 -f8 -o/dev/stdout /dev/stdin"
-                              " | spumux -v0 -mdvd ")
-                          << state->spumux_temp.get_name()
-                          << " > " << vob_temp->get_name();
+           if (encoder_ == mpeg_encoder_ffmpeg)
+           {
+               command_stream
+                   << "ffmpeg"
+                   << " -f image2 -vcodec png -i "
+                   << background_temp_->get_name()
+                   << " -target " << frame_params_.name <<  "-dvd"
+                   << " -vcodec mpeg2video -an -y /dev/stdout"
+                   << " | spumux -v0 -mdvd " << state->spumux_temp.get_name()
+                   << " > " << contents_.menus[menu_num].vob_temp->get_name();
+           }
+           else
+           {
+               assert(encoder_ == mpeg_encoder_mjpegtools_old
+                      || encoder_ == mpeg_encoder_mjpegtools_new);
+               command_stream
+                   << "pngtopnm "
+                   << background_temp_->get_name()
+                   << " | ppmtoy4m -v0 -n1 -F"
+                   << frame_params_.rate_numer
+                   << ":" << frame_params_.rate_denom
+                   << " -A" << frame_params_.pixel_ratio_width
+                   << ":" << frame_params_.pixel_ratio_height
+                   << " -Ip ";
+               // The chroma subsampling keywords changed between
+               // versions 1.6.2 and 1.8 of mjpegtools.  There is no
+               // keyword that works with both.
+               if (encoder_ == mpeg_encoder_mjpegtools_old)
+                   command_stream << "-S420_mpeg2";
+               else
+                   command_stream << "-S420mpeg2";
+               command_stream
+                   << (" | mpeg2enc -v0 -f8 -a2 -o/dev/stdout"
+                       " | mplex -v0 -f8 -o/dev/stdout /dev/stdin"
+                       " | spumux -v0 -mdvd ")
+                   << state->spumux_temp.get_name()
+                   << " > "
+                   << contents_.menus[menu_num].vob_temp->get_name();
+           }
            std::string command(command_stream.str());
            const char * argv[] = {
                "/bin/sh", "-c", command.c_str(), 0
@@ -650,237 +802,6 @@ namespace
                             &command_result);
            if (command_result != 0)
                throw std::runtime_error("spumux pipeline failed");
-
-           page_temp_files_.push_back(vob_temp);
-       }
-    }
-
-    void generate_page_dispatch(std::ostream &, int indent,
-                               int first_page, int last_page);
-
-    void WebDvdWindow::generate_dvd()
-    {
-       temp_file temp("webdvd-dvdauthor-");
-       temp.close();
-       std::ofstream file(temp.get_name().c_str());
-
-       // We generate code that uses registers in the following way:
-       //
-       // g0:     link destination (when jumping to menu 1), then scratch
-       // g1:     current location
-       // g2-g11: location history (g2 = most recent)
-       // g12:    location that last linked to a video
-       //
-       // All locations are divided into two bitfields: the least
-       // significant 10 bits are a page/menu number and the most
-       // significant 6 bits are a link/button number.  This is
-       // chosen for compatibility with the encoding of the s8
-       // (button) register.
-       //
-       static const int link_mult = dvd::reg_s8_button_mult;
-       static const int page_mask = link_mult - 1;
-       static const int link_mask = (1 << dvd::reg_bits) - link_mult;
-
-       file <<
-           "<dvdauthor>\n"
-           "  <vmgm>\n"
-           "    <menus>\n";
-           
-       for (std::size_t page_num = 1;
-            page_num <= page_links_.size();
-            ++page_num)
-       {
-           std::vector<std::string> & page_links =
-               page_links_[page_num - 1];
-
-           if (page_num == 1)
-           {
-               // This is the first page (root menu) which needs to
-               // include initialisation and dispatch code.
-       
-               file <<
-                   "      <pgc entry='title'>\n"
-                   "        <pre>\n"
-                   // Has the location been set yet?
-                   "          if (g1 eq 0)\n"
-                   "          {\n"
-                   // Initialise the current location to first link on
-                   // this page.
-                   "            g1 = " << 1 * link_mult + 1 << ";\n"
-                   "          }\n"
-                   "          else\n"
-                   "          {\n"
-                   // Has the user selected a link?
-                   "            if (g0 ne 0)\n"
-                   "            {\n"
-                   // First update the history.
-                    // Does link go to the last page in the history?
-                   "              if (((g0 ^ g2) &amp; " << page_mask
-                    << ") == 0)\n"
-                    // It does; we treat this as going back and pop the old
-                   // location off the history stack into the current
-                   // location.  Clear the free stack slot.
-                   "              {\n"
-                   "                g1 = g2; g2 = g3; g3 = g4; g4 = g5;\n"
-                   "                g5 = g6; g6 = g7; g7 = g8; g8 = g9;\n"
-                   "                g9 = g10; g10 = g11; g11 = 0;\n"
-                   "              }\n"
-                    "              else\n"
-                   // Link goes to some other page, so push current
-                   // location onto the history stack and set the current
-                   // location to be exactly the target location.
-                   "              {\n"
-                   "                g11 = g10; g10 = g9; g9 = g8; g8 = g7;\n"
-                   "                g7 = g6; g6 = g5; g5 = g4; g4 = g3;\n"
-                   "                g3 = g2; g2 = g1; g1 = g0;\n"
-                   "              }\n"
-                   "            }\n"
-                   // Find the target page number.
-                   "            g0 = g1 &amp; " << page_mask << ";\n";
-               // There seems to be no way to perform a computed jump,
-               // so we generate all possible jumps and a binary search
-               // to select the correct one.
-               generate_page_dispatch(file, 12, 1, page_links_.size());
-               file <<
-                   "          }\n";
-           }
-           else // page_num != 1
-           {
-               file <<
-                   "      <pgc>\n"
-                   "        <pre>\n";
-           }
-
-           file <<
-               // Clear link indicator and highlight the
-               // appropriate link/button.
-               "          g0 = 0; s8 = g1 &amp; " << link_mask << ";\n"
-               "        </pre>\n"
-               "        <vob file='"
-                << page_temp_files_[page_num - 1]->get_name() << "'/>\n";
-
-           for (std::size_t link_num = 1;
-                link_num <= page_links.size();
-                ++link_num)
-           {
-               file <<
-                   "        <button>"
-                   // Update current location.
-                   " g1 = " << link_num * link_mult + page_num << ";";
-
-               // Jump to appropriate resource.
-               const ResourceEntry & resource_loc =
-                   resource_map_[page_links[link_num - 1]];
-               if (resource_loc.first == page_resource)
-                   file <<
-                       " g0 = " << 1 * link_mult + resource_loc.second << ";"
-                       " jump menu 1;";
-               else if (resource_loc.first == video_resource)
-                   file << " jump title " << resource_loc.second << ";";
-
-               file <<  " </button>\n";
-           }
-
-           file << "      </pgc>\n";
-       }
-
-       file <<
-           "    </menus>\n"
-           "  </vmgm>\n";
-
-       // Generate a titleset for each video.  This appears to make
-       // jumping to titles a whole lot simpler.
-       for (std::size_t video_num = 1;
-            video_num <= video_paths_.size();
-            ++video_num)
-       {
-           file <<
-               "  <titleset>\n"
-               // Generate a dummy menu so that the menu button on the
-               // remote control will work.
-               "    <menus>\n"
-               "      <pgc entry='root'>\n"
-               "        <pre> jump vmgm menu; </pre>\n"
-               "      </pgc>\n"
-               "    </menus>\n"
-               "    <titles>\n"
-               "      <pgc>\n"
-               // Record calling page/menu.
-               "        <pre> g12 = g1; </pre>\n"
-               // FIXME: Should XML-escape the path
-               "        <vob file='" << video_paths_[video_num - 1]
-                << "'/>\n"
-               // If page/menu location has not been changed during the
-               // video, change the location to be the following
-               // link/button when returning to it.  In any case,
-               // return to a page/menu.
-               "        <post> if (g1 eq g12) g1 = g1 + " << link_mult
-                << "; call menu; </post>\n"
-               "      </pgc>\n"
-               "    </titles>\n"
-               "  </titleset>\n";
-       }
-
-       file <<
-           "</dvdauthor>\n";
-
-       file.close();
-
-       {
-           const char * argv[] = {
-               "dvdauthor",
-               "-o", output_dir_.c_str(),
-               "-x", temp.get_name().c_str(),
-               0
-           };
-           int command_result;
-           Glib::spawn_sync(".",
-                            Glib::ArrayHandle<std::string>(
-                                argv, sizeof(argv)/sizeof(argv[0]),
-                                Glib::OWNERSHIP_NONE),
-                            Glib::SPAWN_SEARCH_PATH
-                            | Glib::SPAWN_STDOUT_TO_DEV_NULL,
-                            SigC::Slot0<void>(),
-                            0, 0,
-                            &command_result);
-           if (command_result != 0)
-               throw std::runtime_error("dvdauthor failed");
-       }
-    }
-
-    void generate_page_dispatch(std::ostream & file, int indent,
-                               int first_page, int last_page)
-    {
-       if (first_page == 1 && last_page == 1)
-       {
-           // The dispatch code is *on* page 1 so we must not dispatch to
-           // page 1 since that would cause an infinite loop.  This case
-           // should be unreachable if there is more than one page due
-           // to the following case.
-       }
-       else if (first_page == 1 && last_page == 2)
-       {
-           // dvdauthor doesn't allow empty blocks or null statements so
-           // when selecting between pages 1 and 2 we don't use an "else"
-           // part.  We must use braces so that a following "else" will
-           // match the right "if".
-           file << std::setw(indent) << "" << "{\n"
-                << std::setw(indent) << "" << "if (g0 eq 2)\n"
-                << std::setw(indent + 2) << "" << "jump menu 2;\n"
-                << std::setw(indent) << "" << "}\n";
-       }
-       else if (first_page == last_page)
-       {
-           file << std::setw(indent) << ""
-                << "jump menu " << first_page << ";\n";
-       }
-       else
-       {
-           int middle = (first_page + last_page) / 2;
-           file << std::setw(indent) << "" << "if (g0 le " << middle << ")\n";
-           generate_page_dispatch(file, indent + 2, first_page, middle);
-           file << std::setw(indent) << "" << "else\n";
-           generate_page_dispatch(file, indent + 2, middle + 1, last_page);
        }
     }
 
@@ -909,13 +830,54 @@ namespace
 
     void print_usage(std::ostream & stream, const char * command_name)
     {
-       stream << "Usage: " << command_name
-              << (" [gtk-options] [--video-std std-name]"
-                  " [--preview] menu-url [output-dir]\n");
+       stream <<
+           "Usage: " << command_name << " [gtk-options] [--preview]\n"
+           "           [--video-std {ntsc|pal|secam}]\n"
+           "           [--encoder {mjpegtools|mjpegtools-old}]\n"
+           "           menu-url [output-dir]\n");
     }
     
+    void set_browser_preferences()
+    {
+       nsCOMPtr<nsIPrefService> pref_service;
+       static const nsCID pref_service_cid = NS_PREFSERVICE_CID;
+       check(CallGetService<nsIPrefService>(pref_service_cid,
+                                            getter_AddRefs(pref_service)));
+       nsCOMPtr<nsIPrefBranch> pref_branch;
+
+       // Disable IE-compatibility kluge that causes backgrounds to
+       // sometimes/usually be missing from snapshots.  This is only
+       // effective from Mozilla 1.8 onward.
+#      if MOZ_VERSION_MAJOR > 1                                 \
+           || (MOZ_VERSION_MAJOR == 1 && MOZ_VERSION_MINOR >= 8)
+       check(pref_service->GetDefaultBranch("layout",
+                                            getter_AddRefs(pref_branch)));
+       check(pref_branch->SetBoolPref(
+                 "fire_onload_after_image_background_loads",
+                 true));
+#      endif
+
+       // Set display resolution.  With standard-definition video we
+       // will be fitting ~600 pixels across a screen typically
+       // ranging from 10 to 25 inches wide, for a resolution of
+       // 24-60 dpi.  I therefore declare the average horizontal
+       // resolution to be 40 dpi.  The vertical resolution will be
+       // slightly higher (PAL/SECAM) or lower (NTSC), but
+       // unfortunately Mozilla doesn't support non-square pixels
+       // (and neither do fontconfig or Xft anyway).
+       check(pref_service->GetDefaultBranch("browser.display",
+                                            getter_AddRefs(pref_branch)));
+       check(pref_branch->SetIntPref("screen_resolution", 40));
+    }
+
 } // namespace
 
+void fatal_error(const std::string & message)
+{
+    std::cerr << "Fatal error: " << message << "\n";
+    Gtk::Main::quit();
+}
+
 int main(int argc, char ** argv)
 {
     try
@@ -924,6 +886,7 @@ int main(int argc, char ** argv)
        bool preview_mode = false;
        std::string menu_url;
        std::string output_dir;
+       mpeg_encoder encoder = mpeg_encoder_mjpegtools_new;
 
        // Do initial option parsing.  We have to do this before
        // letting Gtk parse the arguments since we may need to spawn
@@ -962,16 +925,17 @@ int main(int argc, char ** argv)
            }
        }
 
-       std::auto_ptr<FrameBuffer> fb;
+       std::auto_ptr<x_frame_buffer> fb;
        if (!preview_mode)
        {
            // Spawn Xvfb and set env variables so that Xlib will use it
            // Use 8 bits each for RGB components, which should translate into
            // "enough" bits for YUV components.
-           fb.reset(new FrameBuffer(frame_params.width, frame_params.height,
-                                    3 * 8));
-           setenv("XAUTHORITY", fb->get_x_authority().c_str(), true);
-           setenv("DISPLAY", fb->get_x_display().c_str(), true);
+           fb.reset(new x_frame_buffer(frame_params.width,
+                                       frame_params.height,
+                                       3 * 8));
+           setenv("XAUTHORITY", fb->get_authority().c_str(), true);
+           setenv("DISPLAY", fb->get_display().c_str(), true);
        }
 
        // Initialise Gtk
@@ -994,6 +958,40 @@ int main(int argc, char ** argv)
            {
                argi += 2;
            }
+           else if (std::strcmp(argv[argi], "--save-temps") == 0)
+           {
+               temp_file::keep_all(true);
+               argi += 1;
+           }
+           else if (std::strcmp(argv[argi], "--encoder") == 0)
+           {
+               if (argi + 1 == argc)
+               {
+                   std::cerr << "Missing argument to --encoder\n";
+                   print_usage(std::cerr, argv[0]);
+                   return EXIT_FAILURE;
+               }
+               if (std::strcmp(argv[argi + 1], "ffmpeg") == 0)
+               {
+                   encoder = mpeg_encoder_ffmpeg;
+               }
+               else if (std::strcmp(argv[argi + 1], "mjpegtools-old") == 0)
+               {
+                   encoder = mpeg_encoder_mjpegtools_old;
+               }
+               else if (std::strcmp(argv[argi + 1], "mjpegtools") == 0
+                        || std::strcmp(argv[argi + 1], "mjpegtools-new") == 0)
+               {
+                   encoder = mpeg_encoder_mjpegtools_new;
+               }
+               else
+               {
+                   std::cerr << "Invalid argument to --encoder\n";
+                   print_usage(std::cerr, argv[0]);
+                   return EXIT_FAILURE;
+               }
+               argi += 2;
+           }
            else if (argv[argi][0] == '-')
            {
                std::cerr << "Invalid option: " << argv[argi] << "\n";
@@ -1030,17 +1028,22 @@ int main(int argc, char ** argv)
            output_dir = argv[argi + 1];
 
        // Initialise Mozilla
-       BrowserWidget::init();
+       browser_widget::initialiser browser_init;
+       set_browser_preferences();
+       if (!preview_mode)
+           null_prompt_service::install();
 
        // Run the browser/converter
-       WebDvdWindow window(frame_params, menu_url, output_dir);
+       webdvd_window window(frame_params, menu_url, output_dir, encoder);
        Gtk::Main::run(window);
+
+       return ((preview_mode || window.is_finished())
+               ? EXIT_SUCCESS
+               : EXIT_FAILURE);
     }
     catch (std::exception & e)
     {
        std::cerr << "Fatal error: " << e.what() << "\n";
        return EXIT_FAILURE;
     }
-
-    return EXIT_SUCCESS;
 }