obs-studio/plugins/obs-transitions/transition-stinger.c

#include <obs-module.h>
#include <util/dstr.h>
#include "util/platform.h"

#define TIMING_TIME 0
#define TIMING_FRAME 1

enum matte_layout {
	MATTE_LAYOUT_HORIZONTAL,
	MATTE_LAYOUT_VERTICAL,
	MATTE_LAYOUT_SEPARATE_FILE,
	MATTE_LAYOUT_MASK,
};

enum fade_style { FADE_STYLE_FADE_OUT_FADE_IN, FADE_STYLE_CROSS_FADE };

struct stinger_info {
	obs_source_t *source;

	obs_source_t *media_source;
	obs_source_t *matte_source;

	uint64_t duration_ns;
	uint64_t duration_frames;
	uint64_t transition_point_ns;
	uint64_t transition_point_frame;
	float transition_point;
	float transition_a_mul;
	float transition_b_mul;
	bool transitioning;
	bool transition_point_is_frame;
	int monitoring_type;
	enum fade_style fade_style;

	bool track_matte_enabled;
	int matte_layout;
	float matte_width_factor;
	float matte_height_factor;
	bool invert_matte;
	bool do_texrender;
	bool matte_rendered;

	gs_effect_t *matte_effect;
	gs_eparam_t *ep_a_tex;
	gs_eparam_t *ep_b_tex;
	gs_eparam_t *ep_matte_tex;
	gs_eparam_t *ep_invert_matte;

	gs_texrender_t *matte_tex;
	gs_texrender_t *stinger_tex;

	float (*mix_a)(void *data, float t);
	float (*mix_b)(void *data, float t);
};

static const char *stinger_get_name(void *type_data)
{
	UNUSED_PARAMETER(type_data);
	return obs_module_text("StingerTransition");
}

static float mix_a_fade_in_out(void *data, float t);
static float mix_b_fade_in_out(void *data, float t);
static float mix_a_cross_fade(void *data, float t);
static float mix_b_cross_fade(void *data, float t);

static void stinger_update(void *data, obs_data_t *settings)
{
	struct stinger_info *s = data;
	const char *path = obs_data_get_string(settings, "path");
	bool hw_decode = obs_data_get_bool(settings, "hw_decode");

	obs_data_t *media_settings = obs_data_create();
	obs_data_set_string(media_settings, "local_file", path);
	obs_data_set_bool(media_settings, "hw_decode", hw_decode);
	obs_data_set_bool(media_settings, "looping", false);

	obs_source_release(s->media_source);
	struct dstr name;
	dstr_init_copy(&name, obs_source_get_name(s->source));
	dstr_cat(&name, " (Stinger)");
	s->media_source = obs_source_create_private("ffmpeg_source", name.array,
						    media_settings);
	dstr_free(&name);
	obs_data_release(media_settings);

	int64_t point = obs_data_get_int(settings, "transition_point");

	s->transition_point_is_frame = obs_data_get_int(settings, "tp_type") ==
				       TIMING_FRAME;

	if (s->transition_point_is_frame)
		s->transition_point_frame = (uint64_t)point;
	else
		s->transition_point_ns = (uint64_t)(point * 1000000LL);

	bool track_matte_was_enabled = s->track_matte_enabled;

	s->track_matte_enabled =
		obs_data_get_bool(settings, "track_matte_enabled");
	s->matte_layout = (int)obs_data_get_int(settings, "track_matte_layout");
	s->matte_width_factor =
		(s->matte_layout == MATTE_LAYOUT_HORIZONTAL ? 2.0f : 1.0f);
	s->matte_height_factor =
		(s->matte_layout == MATTE_LAYOUT_VERTICAL ? 2.0f : 1.0f);
	s->invert_matte = obs_data_get_bool(settings, "invert_matte");

	s->do_texrender = s->track_matte_enabled &&
			  s->matte_layout < MATTE_LAYOUT_SEPARATE_FILE;

	if (s->matte_source) {
		obs_source_release(s->matte_source);
		s->matte_source = NULL;
	}

	if (s->track_matte_enabled &&
	    s->matte_layout == MATTE_LAYOUT_SEPARATE_FILE) {
		const char *tm_path =
			obs_data_get_string(settings, "track_matte_path");

		obs_data_t *tm_media_settings = obs_data_create();
		obs_data_set_string(tm_media_settings, "local_file", tm_path);
		obs_data_set_bool(tm_media_settings, "looping", false);

		s->matte_source = obs_source_create_private(
			"ffmpeg_source", NULL, tm_media_settings);
		obs_data_release(tm_media_settings);

		// no need to output sound from the matte video
		obs_source_set_muted(s->matte_source, true);
	}

	s->monitoring_type =
		(int)obs_data_get_int(settings, "audio_monitoring");
	obs_source_set_monitoring_type(s->media_source, s->monitoring_type);

	s->fade_style =
		(enum fade_style)obs_data_get_int(settings, "audio_fade_style");

	switch (s->fade_style) {
	default:
	case FADE_STYLE_FADE_OUT_FADE_IN:
		s->mix_a = mix_a_fade_in_out;
		s->mix_b = mix_b_fade_in_out;
		break;
	case FADE_STYLE_CROSS_FADE:
		s->mix_a = mix_a_cross_fade;
		s->mix_b = mix_b_cross_fade;
		break;
	}

	if (s->track_matte_enabled != track_matte_was_enabled) {
		obs_enter_graphics();

		gs_texrender_destroy(s->matte_tex);
		gs_texrender_destroy(s->stinger_tex);
		s->matte_tex = NULL;
		s->stinger_tex = NULL;

		if (s->track_matte_enabled) {
			s->matte_tex = gs_texrender_create(GS_RGBA, GS_ZS_NONE);
			s->stinger_tex =
				gs_texrender_create(GS_RGBA, GS_ZS_NONE);
		}

		obs_leave_graphics();
	}
}

static void *stinger_create(obs_data_t *settings, obs_source_t *source)
{
	struct stinger_info *s = bzalloc(sizeof(*s));

	s->source = source;
	s->mix_a = mix_a_fade_in_out;
	s->mix_b = mix_b_fade_in_out;

	char *effect_file = obs_module_file("stinger_matte_transition.effect");
	char *error_string = NULL;
	obs_enter_graphics();
	s->matte_effect =
		gs_effect_create_from_file(effect_file, &error_string);
	obs_leave_graphics();

	if (!s->matte_effect) {
		blog(LOG_ERROR,
		     "Could not open stinger_matte_transition.effect: %s",
		     error_string);
		bfree(error_string);
		bfree(s);
		return NULL;
	}

	bfree(effect_file);

	s->ep_a_tex = gs_effect_get_param_by_name(s->matte_effect, "a_tex");
	s->ep_b_tex = gs_effect_get_param_by_name(s->matte_effect, "b_tex");
	s->ep_matte_tex =
		gs_effect_get_param_by_name(s->matte_effect, "matte_tex");
	s->ep_invert_matte =
		gs_effect_get_param_by_name(s->matte_effect, "invert_matte");

	obs_transition_enable_fixed(s->source, true, 0);
	obs_source_update(source, settings);
	return s;
}

static void stinger_destroy(void *data)
{
	struct stinger_info *s = data;
	obs_source_release(s->media_source);
	obs_source_release(s->matte_source);

	obs_enter_graphics();

	gs_texrender_destroy(s->matte_tex);
	gs_texrender_destroy(s->stinger_tex);
	gs_effect_destroy(s->matte_effect);

	obs_leave_graphics();

	bfree(s);
}

static void stinger_defaults(obs_data_t *settings)
{
	obs_data_set_default_bool(settings, "hw_decode", true);
}

static void stinger_matte_render(void *data, gs_texture_t *a, gs_texture_t *b,
				 float t, uint32_t cx, uint32_t cy)
{
	struct stinger_info *s = data;

	struct vec4 background;
	vec4_zero(&background);

	obs_source_t *matte_source =
		(s->matte_layout == MATTE_LAYOUT_SEPARATE_FILE
			 ? s->matte_source
			 : s->media_source);

	float matte_cx = (float)obs_source_get_width(matte_source) /
			 s->matte_width_factor;
	float matte_cy = (float)obs_source_get_height(matte_source) /
			 s->matte_height_factor;

	float width_offset = (s->matte_layout == MATTE_LAYOUT_HORIZONTAL
				      ? (-matte_cx)
				      : 0.0f);
	float height_offset =
		(s->matte_layout == MATTE_LAYOUT_VERTICAL ? (-matte_cy) : 0.0f);

	// Track matte media render
	if (matte_cx > 0 && matte_cy > 0) {
		float scale_x = (float)cx / matte_cx;
		float scale_y = (float)cy / matte_cy;

		if (gs_texrender_begin(s->matte_tex, cx, cy)) {
			gs_matrix_scale3f(scale_x, scale_y, 1.0f);
			gs_matrix_translate3f(width_offset, height_offset,
					      0.0f);
			gs_clear(GS_CLEAR_COLOR, &background, 0.0f, 0);
			gs_ortho(0.0f, (float)cx, 0.0f, (float)cy, -100.0f,
				 100.0f);

			obs_source_video_render(matte_source);

			gs_texrender_end(s->matte_tex);
		}
	}

	const bool previous = gs_framebuffer_srgb_enabled();
	gs_enable_framebuffer_srgb(true);

	gs_effect_set_texture(s->ep_a_tex, a);
	gs_effect_set_texture(s->ep_b_tex, b);
	gs_effect_set_texture(s->ep_matte_tex,
			      gs_texrender_get_texture(s->matte_tex));
	gs_effect_set_bool(s->ep_invert_matte, s->invert_matte);

	while (gs_effect_loop(s->matte_effect, "StingerMatte"))
		gs_draw_sprite(NULL, 0, cx, cy);

	gs_enable_framebuffer_srgb(previous);

	UNUSED_PARAMETER(t);
}

static void stinger_texrender(struct stinger_info *s, uint32_t source_cx,
			      uint32_t source_cy, uint32_t media_cx,
			      uint32_t media_cy)
{
	if (gs_texrender_begin(s->stinger_tex, source_cx, source_cy)) {
		float cx = (float)media_cx / s->matte_width_factor;
		float cy = (float)media_cy / s->matte_height_factor;

		gs_ortho(0.0f, cx, 0.0f, cy, -100.0f, 100.0f);

		gs_blend_state_push();
		gs_enable_blending(false);
		obs_source_video_render(s->media_source);
		gs_blend_state_pop();

		gs_texrender_end(s->stinger_tex);
	}
}

static void stinger_video_render(void *data, gs_effect_t *effect)
{
	struct stinger_info *s = data;

	uint32_t media_cx = obs_source_get_width(s->media_source);
	uint32_t media_cy = obs_source_get_height(s->media_source);

	if (s->track_matte_enabled) {
		bool ready = obs_source_active(s->media_source) && !!media_cx &&
			     !!media_cy;
		if (ready) {
			if (!s->matte_rendered)
				s->matte_rendered = true;
			obs_transition_video_render(s->source,
						    stinger_matte_render);
		} else {
			obs_transition_video_render_direct(
				s->source, s->matte_rendered
						   ? OBS_TRANSITION_SOURCE_B
						   : OBS_TRANSITION_SOURCE_A);
		}
		if (s->matte_layout == MATTE_LAYOUT_MASK)
			return;
	} else {
		float t = obs_transition_get_time(s->source);
		bool use_a = t < s->transition_point;

		enum obs_transition_target target =
			use_a ? OBS_TRANSITION_SOURCE_A
			      : OBS_TRANSITION_SOURCE_B;

		if (!obs_transition_video_render_direct(s->source, target))
			return;
	}

	/* --------------------- */

	uint32_t source_cx = obs_source_get_width(s->source);
	uint32_t source_cy = obs_source_get_height(s->source);

	float source_cxf = (float)source_cx;
	float source_cyf = (float)source_cy;

	if (!media_cx || !media_cy)
		return;

	if (s->do_texrender) {
		stinger_texrender(s, source_cx, source_cy, media_cx, media_cy);

		gs_effect_t *e = obs_get_base_effect(OBS_EFFECT_DEFAULT);
		gs_eparam_t *p = gs_effect_get_param_by_name(e, "image");
		gs_texture_t *tex = gs_texrender_get_texture(s->stinger_tex);

		gs_effect_set_texture(p, tex);
		while (gs_effect_loop(e, "Draw"))
			gs_draw_sprite(NULL, 0, source_cx, source_cy);
	} else {
		gs_matrix_push();
		gs_matrix_scale3f(source_cxf / (float)media_cx,
				  source_cyf / (float)media_cy, 1.0f);
		obs_source_video_render(s->media_source);
		gs_matrix_pop();
	}

	UNUSED_PARAMETER(effect);
}

static void stinger_video_tick(void *data, float seconds)
{
	struct stinger_info *s = data;

	if (s->track_matte_enabled) {
		gs_texrender_reset(s->stinger_tex);
		gs_texrender_reset(s->matte_tex);
	}

	UNUSED_PARAMETER(seconds);
}

static inline float calc_fade(float t, float mul)
{
	t *= mul;
	return t > 1.0f ? 1.0f : t;
}

static float mix_a_fade_in_out(void *data, float t)
{
	struct stinger_info *s = data;
	return 1.0f - calc_fade(t, s->transition_a_mul);
}

static float mix_b_fade_in_out(void *data, float t)
{
	struct stinger_info *s = data;
	return 1.0f - calc_fade(1.0f - t, s->transition_b_mul);
}

static float mix_a_cross_fade(void *data, float t)
{
	UNUSED_PARAMETER(data);
	return 1.0f - t;
}

static float mix_b_cross_fade(void *data, float t)
{
	UNUSED_PARAMETER(data);
	return t;
}

static bool stinger_audio_render(void *data, uint64_t *ts_out,
				 struct obs_source_audio_mix *audio,
				 uint32_t mixers, size_t channels,
				 size_t sample_rate)
{
	struct stinger_info *s = data;
	uint64_t ts = 0;

	if (!s) {
		return false;
	}

	if (!obs_source_audio_pending(s->media_source)) {
		ts = obs_source_get_audio_timestamp(s->media_source);
		if (!ts)
			return false;
	}

	bool success = obs_transition_audio_render(s->source, ts_out, audio,
						   mixers, channels,
						   sample_rate, s->mix_a,
						   s->mix_b);
	if (!ts)
		return success;

	if (!*ts_out || ts < *ts_out)
		*ts_out = ts;

	struct obs_source_audio_mix child_audio;
	obs_source_get_audio_mix(s->media_source, &child_audio);

	for (size_t mix = 0; mix < MAX_AUDIO_MIXES; mix++) {
		if ((mixers & (1 << mix)) == 0)
			continue;

		for (size_t ch = 0; ch < channels; ch++) {
			register float *out = audio->output[mix].data[ch];
			register float *in = child_audio.output[mix].data[ch];
			register float *end = in + AUDIO_OUTPUT_FRAMES;

			while (in < end)
				*(out++) += *(in++);
		}
	}

	return true;
}

static void stinger_transition_start(void *data)
{
	struct stinger_info *s = data;

	if (s->media_source) {
		calldata_t cd = {0};

		proc_handler_t *ph =
			obs_source_get_proc_handler(s->media_source);
		proc_handler_t *matte_ph =
			s->matte_source
				? obs_source_get_proc_handler(s->matte_source)
				: NULL;

		if (s->transitioning) {
			proc_handler_call(ph, "restart", &cd);
			if (matte_ph) {
				proc_handler_call(matte_ph, "restart", &cd);
			}
			return;
		}

		s->matte_rendered = false;

		proc_handler_call(ph, "get_duration", &cd);
		proc_handler_call(ph, "get_nb_frames", &cd);
		s->duration_ns =
			(uint64_t)calldata_int(&cd, "duration") + 250000000ULL;
		s->duration_frames = (uint64_t)calldata_int(&cd, "num_frames");

		if (s->transition_point_is_frame)
			s->transition_point =
				(float)((long double)s->transition_point_frame /
					(long double)s->duration_frames);
		else
			s->transition_point =
				(float)((long double)s->transition_point_ns /
					(long double)s->duration_ns);

		if (s->transition_point > 0.999f)
			s->transition_point = 0.999f;
		else if (s->transition_point < 0.001f)
			s->transition_point = 0.001f;

		s->transition_a_mul = (1.0f / s->transition_point);
		s->transition_b_mul = (1.0f / (1.0f - s->transition_point));

		if (s->track_matte_enabled && s->matte_source) {
			proc_handler_call(matte_ph, "get_duration", &cd);
			uint64_t tm_duration_ns =
				(uint64_t)calldata_int(&cd, "duration");

			s->duration_ns = ((tm_duration_ns > s->duration_ns)
						  ? (tm_duration_ns)
						  : (s->duration_ns));

			obs_source_add_active_child(s->source, s->matte_source);
		}

		obs_transition_enable_fixed(
			s->source, true, (uint32_t)(s->duration_ns / 1000000));

		calldata_free(&cd);

		obs_source_add_active_child(s->source, s->media_source);
	}

	s->transitioning = true;
}

static void stinger_transition_stop(void *data)
{
	struct stinger_info *s = data;

	if (s->media_source)
		obs_source_remove_active_child(s->source, s->media_source);

	if (s->matte_source)
		obs_source_remove_active_child(s->source, s->matte_source);

	s->transitioning = false;
}

static void stinger_enum_active_sources(void *data,
					obs_source_enum_proc_t enum_callback,
					void *param)
{
	struct stinger_info *s = data;
	if (s->media_source && s->transitioning)
		enum_callback(s->source, s->media_source, param);

	if (s->matte_source && s->transitioning)
		enum_callback(s->source, s->matte_source, param);
}

static void stinger_enum_all_sources(void *data,
				     obs_source_enum_proc_t enum_callback,
				     void *param)
{
	struct stinger_info *s = data;
	if (s->media_source)
		enum_callback(s->source, s->media_source, param);

	if (s->matte_source)
		enum_callback(s->source, s->matte_source, param);
}

#define FILE_FILTER " (*.mp4 *.ts *.mov *.wmv *.flv *.mkv *.avi *.gif *.webm);;"

static bool transition_point_type_modified(obs_properties_t *ppts,
					   obs_property_t *p, obs_data_t *s)
{
	int64_t type = obs_data_get_int(s, "tp_type");

	obs_property_t *prop_transition_point =
		obs_properties_get(ppts, "transition_point");

	if (type == TIMING_TIME) {
		obs_property_set_description(
			prop_transition_point,
			obs_module_text("TransitionPoint"));
	} else {
		obs_property_set_description(
			prop_transition_point,
			obs_module_text("TransitionPointFrame"));
	}

	bool uses_ms_prefix = (type == TIMING_TIME);
	obs_property_int_set_suffix(p, (uses_ms_prefix ? " ms" : ""));

	return true;
}

static bool track_matte_layout_modified(obs_properties_t *ppts,
					obs_property_t *p, obs_data_t *s)
{
	int matte_layout = (int)obs_data_get_int(s, "track_matte_layout");
	obs_property_t *prop_matte_path =
		obs_properties_get(ppts, "track_matte_path");

	bool uses_separate_file = (matte_layout == MATTE_LAYOUT_SEPARATE_FILE);
	obs_property_set_visible(prop_matte_path, uses_separate_file);

	UNUSED_PARAMETER(p);
	return true;
}

static bool track_matte_enabled_modified(obs_properties_t *ppts,
					 obs_property_t *p, obs_data_t *s)
{
	bool track_matte_enabled = obs_data_get_bool(s, "track_matte_enabled");
	obs_property_t *prop_tp_type = obs_properties_get(ppts, "tp_type");

	if (track_matte_enabled) {
		obs_property_set_description(
			prop_tp_type,
			obs_module_text("AudioTransitionPointType"));
	} else {
		obs_property_set_description(
			prop_tp_type, obs_module_text("TransitionPointType"));
	}

	UNUSED_PARAMETER(p);
	return true;
}

static obs_properties_t *stinger_properties(void *data)
{
	obs_properties_t *ppts = obs_properties_create();
	struct dstr filter = {0};

	obs_properties_set_flags(ppts, OBS_PROPERTIES_DEFER_UPDATE);

	dstr_copy(&filter, obs_module_text("FileFilter.VideoFiles"));
	dstr_cat(&filter, FILE_FILTER);
	dstr_cat(&filter, obs_module_text("FileFilter.AllFiles"));
	dstr_cat(&filter, " (*.*)");

	// main stinger settings
	obs_properties_add_path(ppts, "path", obs_module_text("VideoFile"),
				OBS_PATH_FILE, filter.array, NULL);

	obs_property_t *p = obs_properties_add_list(
		ppts, "tp_type", obs_module_text("TransitionPointType"),
		OBS_COMBO_TYPE_LIST, OBS_COMBO_FORMAT_INT);
	obs_properties_add_bool(ppts, "hw_decode",
				obs_module_text("HardwareDecode"));
	obs_property_list_add_int(p, obs_module_text("TransitionPointTypeTime"),
				  TIMING_TIME);
	obs_property_list_add_int(
		p, obs_module_text("TransitionPointTypeFrame"), TIMING_FRAME);

	obs_property_set_modified_callback(p, transition_point_type_modified);

	obs_properties_add_int(ppts, "transition_point",
			       obs_module_text("TransitionPoint"), 0, 120000,
			       1);

	// track matte properties
	{
		obs_properties_t *track_matte_group = obs_properties_create();

		p = obs_properties_add_list(track_matte_group,
					    "track_matte_layout",
					    obs_module_text("TrackMatteLayout"),
					    OBS_COMBO_TYPE_LIST,
					    OBS_COMBO_FORMAT_INT);
		obs_property_list_add_int(
			p, obs_module_text("TrackMatteLayoutHorizontal"),
			MATTE_LAYOUT_HORIZONTAL);
		obs_property_list_add_int(
			p, obs_module_text("TrackMatteLayoutVertical"),
			MATTE_LAYOUT_VERTICAL);

		/* TODO: Requires way to synchronize or combine two media files
		 * together */
#if 0
		obs_property_list_add_int(
			p, obs_module_text("TrackMatteLayoutSeparateFile"),
			MATTE_LAYOUT_SEPARATE_FILE);
#endif
		obs_property_list_add_int(
			p, obs_module_text("TrackMatteLayoutMask"),
			MATTE_LAYOUT_MASK);

		obs_property_set_modified_callback(p,
						   track_matte_layout_modified);

		obs_properties_add_path(track_matte_group, "track_matte_path",
					obs_module_text("TrackMatteVideoFile"),
					OBS_PATH_FILE, filter.array, NULL);

		obs_properties_add_bool(track_matte_group, "invert_matte",
					obs_module_text("InvertTrackMatte"));

		p = obs_properties_add_group(
			ppts, "track_matte_enabled",
			obs_module_text("TrackMatteEnabled"),
			OBS_GROUP_CHECKABLE, track_matte_group);

		obs_property_set_modified_callback(
			p, track_matte_enabled_modified);
	}
	dstr_free(&filter);

	// audio output settings
	obs_property_t *monitor_list = obs_properties_add_list(
		ppts, "audio_monitoring", obs_module_text("AudioMonitoring"),
		OBS_COMBO_TYPE_LIST, OBS_COMBO_FORMAT_INT);
	obs_property_list_add_int(monitor_list,
				  obs_module_text("AudioMonitoring.None"),
				  OBS_MONITORING_TYPE_NONE);
	obs_property_list_add_int(
		monitor_list, obs_module_text("AudioMonitoring.MonitorOnly"),
		OBS_MONITORING_TYPE_MONITOR_ONLY);
	obs_property_list_add_int(monitor_list,
				  obs_module_text("AudioMonitoring.Both"),
				  OBS_MONITORING_TYPE_MONITOR_AND_OUTPUT);

	// audio fade settings
	obs_property_t *audio_fade_style = obs_properties_add_list(
		ppts, "audio_fade_style", obs_module_text("AudioFadeStyle"),
		OBS_COMBO_TYPE_LIST, OBS_COMBO_FORMAT_INT);
	obs_property_list_add_int(
		audio_fade_style,
		obs_module_text("AudioFadeStyle.FadeOutFadeIn"),
		FADE_STYLE_FADE_OUT_FADE_IN);
	obs_property_list_add_int(audio_fade_style,
				  obs_module_text("AudioFadeStyle.CrossFade"),
				  FADE_STYLE_CROSS_FADE);

	UNUSED_PARAMETER(data);
	return ppts;
}

static void missing_file_callback(void *src, const char *new_path, void *data)
{
	struct stinger_info *s = src;
	obs_data_t *settings = obs_source_get_settings(s->source);

	const char *type = data;

	if (strcmp(type, "media_source") == 0) {
		obs_data_set_string(settings, "path", new_path);
	} else if (strcmp(type, "matte_source") == 0) {
		obs_data_set_string(settings, "track_matte_path", new_path);
	}

	obs_source_update(s->source, settings);
	obs_data_release(settings);
}

static obs_missing_files_t *stinger_missing_files(void *data)
{
	struct stinger_info *s = data;
	obs_data_t *settings = obs_source_get_settings(s->source);
	obs_missing_files_t *files = obs_missing_files_create();

	const char *path = obs_data_get_string(settings, "path");

	if (strcmp(path, "") != 0) {
		if (!os_file_exists(path)) {
			obs_missing_file_t *file = obs_missing_file_create(
				path, missing_file_callback,
				OBS_MISSING_FILE_SOURCE, s->source,
				(void *)"media_source");

			obs_missing_files_add_file(files, file);
		}
	}

	const char *track_matte_path =
		obs_data_get_string(settings, "track_matte_path");

	if (strcmp(track_matte_path, "") != 0) {
		if (!os_file_exists(track_matte_path)) {
			obs_missing_file_t *file = obs_missing_file_create(
				track_matte_path, missing_file_callback,
				OBS_MISSING_FILE_SOURCE, s->source,
				(void *)"matte_source");

			obs_missing_files_add_file(files, file);
		}
	}

	obs_data_release(settings);
	return files;
}

struct obs_source_info stinger_transition = {
	.id = "obs_stinger_transition",
	.type = OBS_SOURCE_TYPE_TRANSITION,
	.get_name = stinger_get_name,
	.create = stinger_create,
	.destroy = stinger_destroy,
	.update = stinger_update,
	.get_defaults = stinger_defaults,
	.video_render = stinger_video_render,
	.video_tick = stinger_video_tick,
	.audio_render = stinger_audio_render,
	.missing_files = stinger_missing_files,
	.get_properties = stinger_properties,
	.enum_active_sources = stinger_enum_active_sources,
	.enum_all_sources = stinger_enum_all_sources,
	.transition_start = stinger_transition_start,
	.transition_stop = stinger_transition_stop,
};