Re: [PATCH 3/3] winegstreamer: Implement IMFMediaStream::GetStreamDescriptor.

[Derek Lesho]

On 9/9/20 7:00 PM, Zebediah Figura wrote:
> On 9/8/20 10:47 AM, Derek Lesho wrote:
> > Signed-off-by: Derek Lesho
> >
> > dlls/winegstreamer/gst_cbs.c      |  13 ++
> >   dlls/winegstreamer/gst_cbs.h      |   8 ++
> >   dlls/winegstreamer/gst_private.h  |   5 +
> >   dlls/winegstreamer/media_source.c | 137 +++++++++++++++++++-
> >   dlls/winegstreamer/mfplat.c       | 208 ++++++++++++++++++++++++++++++
> >   5 files changed, 368 insertions(+), 3 deletions(-)
> >
> > diff --git a/dlls/winegstreamer/gst_cbs.c b/dlls/winegstreamer/gst_cbs.c
> > index 4755f5b42f1..e56c987eb38 100644
> > --- a/dlls/winegstreamer/gst_cbs.c
> > +++ b/dlls/winegstreamer/gst_cbs.c
> > @@ -404,3 +404,16 @@ void source_all_streams_wrapper(GstElement *element, gpointer user)
> >   call_cb(&cbdata);
> >
> > }
> > -
> >
> > +GstPadProbeReturn caps_listener_wrapper(GstPad *pad, GstPadProbeInfo *info, gpointer user)
> > +{
> > - struct cb_data cbdata = { STREAM_PAD_EVENT };
> > -
> > - cbdata.u.pad_probe_data.pad = pad;
> > - cbdata.u.pad_probe_data.info = info;
> > - cbdata.u.pad_probe_data.user = user;
> > -
> > - call_cb(&cbdata);
> > -
> > - return cbdata.u.pad_probe_data.ret;
> >
> > +}
> > diff --git a/dlls/winegstreamer/gst_cbs.h b/dlls/winegstreamer/gst_cbs.h
> > index d87cc8c21e9..7173c09746e 100644
> > --- a/dlls/winegstreamer/gst_cbs.h
> > +++ b/dlls/winegstreamer/gst_cbs.h
> > @@ -52,6 +52,7 @@ enum CB_TYPE {
> >       SOURCE_STREAM_ADDED,
> >       SOURCE_STREAM_REMOVED,
> >       SOURCE_ALL_STREAMS,
> > - STREAM_PAD_EVENT,
> >  MEDIA_SOURCE_MAX,
> > };
> >
> > @@ -137,6 +138,12 @@ struct cb_data {
> >               GstQuery *query;
> >               gboolean ret;
> >           } query_sink_data;
> > -
> >    struct pad_probe_data {
> > -
> >        GstPad *pad;
> > -
> >        GstPadProbeInfo *info;
> > -
> >        gpointer user;
> > -
> >        GstPadProbeReturn ret;
> > -
> >    } pad_probe_data;
> > } u;
> >
> > int finished;
> >
> > @@ -172,5 +179,6 @@ GstBusSyncReply watch_source_bus_wrapper(GstBus *bus, GstMessage *message, gpoin
> >   void source_stream_added_wrapper(GstElement *bin, GstPad *pad, gpointer user) DECLSPEC_HIDDEN;
> >   void source_stream_removed_wrapper(GstElement *element, GstPad *pad, gpointer user) DECLSPEC_HIDDEN;
> >   void source_all_streams_wrapper(GstElement *element, gpointer user) DECLSPEC_HIDDEN;
> > +GstPadProbeReturn caps_listener_wrapper(GstPad *pad, GstPadProbeInfo *info, gpointer user);
> >
> > #endif
> > diff --git a/dlls/winegstreamer/gst_private.h b/dlls/winegstreamer/gst_private.h
> > index ef07d3591e7..86392eea4e3 100644
> > --- a/dlls/winegstreamer/gst_private.h
> > +++ b/dlls/winegstreamer/gst_private.h
> > @@ -36,6 +36,7 @@
> >   #include "winuser.h"
> >   #include "dshow.h"
> >   #include "strmif.h"
> > +#include "mfobjects.h"
> >   #include "wine/heap.h"
> >   #include "wine/strmbase.h"
> >
> > @@ -54,6 +55,10 @@ void start_dispatch_thread(void) DECLSPEC_HIDDEN;
> >
> > extern HRESULT mfplat_get_class_object(REFCLSID rclsid, REFIID riid, void **obj) DECLSPEC_HIDDEN;
> >
> > +HRESULT winegstreamer_stream_handler_create(REFIID riid, void **obj) DECLSPEC_HIDDEN;
> > +GstCaps *make_mf_compatible_caps(GstCaps *caps);
> > +IMFMediaType *mf_media_type_from_caps(GstCaps *caps);
>
> Missing DECLSPEC_HIDDEN.

👌
> > -
> >
> > HRESULT winegstreamer_stream_handler_create(REFIID riid, void **obj) DECLSPEC_HIDDEN;
> >
> > #endif /* __GST_PRIVATE_INCLUDED__ */
> >
> > diff --git a/dlls/winegstreamer/media_source.c b/dlls/winegstreamer/media_source.c
> > index 29af2b72def..345b1fe4528 100644
> > --- a/dlls/winegstreamer/media_source.c
> > +++ b/dlls/winegstreamer/media_source.c
> > @@ -47,14 +47,19 @@ struct media_stream
> >       LONG ref;
> >       struct media_source *parent_source;
> >       IMFMediaEventQueue *event_queue;
> > -
> >
> > IMFStreamDescriptor *descriptor;
> >  GstElement *appsink;
> >  GstPad *their_src, *my_sink;
> > -
> >
> > GstCaps *their_caps;
> >  enum
> >  {
> >      STREAM_STUB,
> >      STREAM_INACTIVE,
> >      STREAM_SHUTDOWN,
> >  } state;
> > -
> >
> > /* used when in STUB state: */
> > -
> >
> > DWORD stream_id;
> > -
> >
> > HANDLE caps_event;
> > };
> >
> > struct media_source
> >
> > @@ -312,6 +317,8 @@ static ULONG WINAPI media_stream_Release(IMFMediaStream *iface)
> >       {
> >           if (stream->my_sink)
> >               gst_object_unref(GST_OBJECT(stream->my_sink));
> > -
> >    if (stream->descriptor)
> > -
> >        IMFStreamDescriptor_Release(stream->descriptor);
> >     if (stream->event_queue)
> >         IMFMediaEventQueue_Release(stream->event_queue);
> >     if (stream->parent_source)
> >
> > @@ -393,7 +400,10 @@ static HRESULT WINAPI media_stream_GetStreamDescriptor(IMFMediaStream* iface, IM
> >       if (stream->state == STREAM_SHUTDOWN)
> >           return MF_E_SHUTDOWN;
> > - return E_NOTIMPL;
> > -
> >
> > IMFStreamDescriptor_AddRef(stream->descriptor);
> > -
> >
> > *descriptor = stream->descriptor;
> > -
> > -
> >
> > return S_OK;
> > }
> >
> > static HRESULT WINAPI media_stream_RequestSample(IMFMediaStream *iface, IUnknown *token)
> >
> > @@ -436,9 +446,12 @@ static HRESULT new_media_stream(struct media_source *source, GstPad *pad, DWORD
> >       IMFMediaSource_AddRef(&source->IMFMediaSource_iface);
> >       object->parent_source = source;
> >       object->their_src = pad;
> > -
> >
> > object->stream_id = stream_id;
> >
> > object->state = STREAM_STUB;
> > -
> >
> > object->caps_event = CreateEventA(NULL, TRUE, FALSE, NULL);
> > -
> > if (FAILED(hr = MFCreateEventQueue(&object->event_queue)))
> >     goto fail;
> >
> > @@ -455,10 +468,10 @@ static HRESULT new_media_stream(struct media_source *source, GstPad *pad, DWORD
> >       g_object_set(object->appsink, "wait-on-eos", FALSE, NULL);
> >   object->my_sink = gst_element_get_static_pad(object->appsink, "sink");
> > - gst_pad_set_element_private(object->my_sink, object);
> > -
> > gst_pad_link(object->their_src, object->my_sink);
> >
> > -
> >
> > gst_pad_add_probe(object->my_sink, GST_PAD_PROBE_TYPE_EVENT_DOWNSTREAM, caps_listener_wrapper, object, NULL);
> > -
> > gst_element_sync_state_with_parent(object->appsink);
> >
> > TRACE("->(%p)\n", object);
> >
> > @@ -473,6 +486,43 @@ static HRESULT new_media_stream(struct media_source *source, GstPad *pad, DWORD
> >       return hr;
> >   }
> >
> > +static HRESULT media_stream_init_desc(struct media_stream *stream)
> > +{
> > - HRESULT hr;
> > - IMFMediaTypeHandler *type_handler;
> > - IMFMediaType *stream_type = NULL;
> > -
> > - stream->their_caps = gst_caps_fixate(stream->their_caps);
>
> I think this is unnecessary; the caps should already be fixed.

👌
> > -
> > - stream_type = mf_media_type_from_caps(stream->their_caps);
> > - gst_caps_unref(stream->their_caps);
>
> This seems a bit error-prone. I'd suggest getting rid of the field and
> instead calling gst_caps_copy(gst_pad_get_current_caps(...))

Can we be sure that the caps will be set after the pad probe callback is 
complete?
> > - if (!stream_type)
> > - {
> > -
> >    hr = E_FAIL;
> > -
> >    goto fail;
> > - }
> > -
> > - if (FAILED(hr = MFCreateStreamDescriptor(stream->stream_id, 1, &stream_type, &stream->descriptor)))
> > -
> >    goto fail;
> > -
> > - if (FAILED(hr = IMFStreamDescriptor_GetMediaTypeHandler(stream->descriptor, &type_handler)))
> > -
> >    goto fail;
> > -
> > - if (FAILED(hr = IMFMediaTypeHandler_SetCurrentMediaType(type_handler, stream_type)))
> > -
> >    goto fail;
> > -
> > - IMFMediaTypeHandler_Release(type_handler);
> > -
> > - stream->state = STREAM_INACTIVE;
> > -
> > - return S_OK;
> > - fail:
> > - ERR("media stream initialization failed with %x\n", hr);
>
> While this does tell you that one of the mfplat functions failed, it
> doesn't actually tell you which one. There's similar patterns elsewhere
> in this series.

Is that a problem?  The likelyhood of one of these functions failing is 
very slim, and in that case, you could use use +mfplat to see the last 
function to run before the error.  If conversion to a media type failed, 
the relevant conversion function will also emit an error.
> > - if (type_handler)
> > -
> >    IMFMediaTypeHandler_Release(type_handler);
> > - return hr;
> >
> > +}
> > - static HRESULT WINAPI media_source_QueryInterface(IMFMediaSource *iface, REFIID riid, void **out)
> > {
> >     struct media_source *source = impl_from_IMFMediaSource(iface);
> >
> > @@ -680,6 +730,23 @@ static const IMFMediaSourceVtbl IMFMediaSource_vtbl =
> >       media_source_Shutdown,
> >   };
> >
> > +/* If this callback is extended to use any significant win32 APIs, a wrapper function
> > - should be added */
> >
> > +gboolean stream_found(GstElement *bin, GstPad *pad, GstCaps *caps, gpointer user)
> > +{
> > - GstCaps *target_caps;
> > -
> > - /* if the stream can be converted into an MF compatible type, we'll go that route
> > -
> >   otherwise, we'll rely on decodebin for the whole process */
> > -
>
> I think we should leave this part out for now.

I disagree, without it, a lot of compressed media type conversion code 
becomes dead, and this codepath which this triggers is closer to the 
windows one.
> > - if ((target_caps = make_mf_compatible_caps(caps)))
> > - {
> > -
> >    gst_caps_unref(target_caps);
> > -
> >    return FALSE;
> > - }
> > - return TRUE;
> >
> > +}
> > - static void source_stream_added(GstElement *element, GstPad *pad, gpointer user)
> > {
> >     struct media_source *source = (struct media_source *) user;
> >
> > @@ -697,6 +764,36 @@ static void source_stream_added(GstElement *element, GstPad *pad, gpointer user)
> >   TRACE("stream-id: %u\n", stream_id);
> >
> > - /* This codepath is currently never triggered, as we don't need to ever restart the gstreamer pipeline.  It is retained in
> > -
> >   case this becomes necessary in the future, for example in a case where different media types require different
> > -
> >   post-processing elements. */
>
> In general, if a code path is dead, it shouldn't be introduced (yet).

👌
> > - for (unsigned int i = 0; i < source->stream_count; i++)
> > - {
> > -
> >    DWORD existing_stream_id;
> > -
> >    IMFStreamDescriptor *descriptor = source->streams[i]->descriptor;
> > -
> > -
> >    if (source->streams[i]->state == STREAM_STUB)
> > -
> >        continue;
> > -
> > -
> >    if (FAILED(IMFStreamDescriptor_GetStreamIdentifier(descriptor, &existing_stream_id)))
> > -
> >        goto leave;
> > -
> > -
> >    if (existing_stream_id == stream_id)
> > -
> >    {
> > -
> >        struct media_stream *existing_stream = source->streams[i];
> > -
> >        GstPadLinkReturn ret;
> > -
> > -
> >        TRACE("Found existing stream %p\n", existing_stream);
> > -
> > -
> >        existing_stream->their_src = pad;
> > -
> > -
> >        if ((ret = gst_pad_link(existing_stream->their_src, existing_stream->my_sink)) != GST_PAD_LINK_OK)
> > -
> >            ERR("Error linking decodebin pad to stream %p, err = %d\n", existing_stream, ret);
> > -
> > -
> >        goto leave;
> > -
> >    }
> > - }
> > -
> > if (FAILED(new_media_stream(source, pad, stream_id, &stream)))
> > {
> >     goto leave;
> >
> > @@ -737,6 +834,26 @@ static void source_all_streams(GstElement *element, gpointer user)
> >       SetEvent(source->all_streams_event);
> >   }
> >
> > +static GstPadProbeReturn caps_listener(GstPad *pad, GstPadProbeInfo *info, gpointer user)
> > +{
> > - struct media_stream *stream = (struct media_stream *) user;
>
> The cast is unnecessary, here and elsewhere.

👌
> > - GstEvent *event = gst_pad_probe_info_get_event(info);
> > -
> > - if (GST_EVENT_TYPE(event) == GST_EVENT_CAPS)
> > - {
> > -
> >    GstCaps *caps;
> > -
> >    TRACE("got caps for stream %p\n", stream);
> > -
> > -
> >    gst_event_parse_caps(event, &caps);
> > -
> >    stream->their_caps = gst_caps_copy(caps);
> > -
> >    SetEvent(stream->caps_event);
> > -
> > -
> >    return GST_PAD_PROBE_REMOVE;
> > - }
> > -
> > - return GST_PAD_PROBE_OK;
> >
> > +}
> > - static HRESULT media_source_constructor(IMFByteStream *bytestream, struct media_source **out_media_source)
> > {
> >     GstStaticPadTemplate src_template = GST_STATIC_PAD_TEMPLATE(
> >
> > @@ -787,6 +904,8 @@ static HRESULT media_source_constructor(IMFByteStream *bytestream, struct media_
> >   gst_bin_add(GST_BIN(object->container), object->decodebin);
> >
> > - if(!GetEnvironmentVariableA("MF_DECODE_IN_SOURCE", NULL, 0))
>
> Debugging code?

Yeah, it's useful for finding out whether an issue is caused by the real 
decoder MFT path, or topology loader.  (As it skips all that)
> > -
> >    g_signal_connect(object->decodebin, "autoplug-continue", G_CALLBACK(stream_found), object);
> > g_signal_connect(object->decodebin, "pad-added", G_CALLBACK(source_stream_added_wrapper), object);
> > g_signal_connect(object->decodebin, "pad-removed", G_CALLBACK(source_stream_removed_wrapper), object);
> > g_signal_connect(object->decodebin, "no-more-pads", G_CALLBACK(source_all_streams_wrapper), object);
> >
> > @@ -812,6 +931,12 @@ static HRESULT media_source_constructor(IMFByteStream *bytestream, struct media_
> >       }
> >   WaitForSingleObject(object->all_streams_event, INFINITE);
> > - for (unsigned int i = 0; i < object->stream_count; i++)
>
> Misplaced declaration.

👌
> > -
> >
> > {
> > -
> >    WaitForSingleObject(object->streams[i]->caps_event, INFINITE);
> > -
> >    if (FAILED(hr = media_stream_init_desc(object->streams[i])))
> > -
> >        goto fail;
> > -
> >
> > }
> >
> > object->state = SOURCE_STOPPED;
> >
> > @@ -1337,6 +1462,12 @@ void perform_cb_media_source(struct cb_data *cbdata)
> >               source_all_streams(data->element, data->user);
> >               break;
> >           }
> > - case STREAM_PAD_EVENT:
> > -
> >    {
> > -
> >        struct pad_probe_data *data = &cbdata->u.pad_probe_data;
> > -
> >        cbdata->u.pad_probe_data.ret = caps_listener(data->pad, data->info, data->user);
> > -
> >        break;
> > -
> >    }
> > default:
> >     {
> >         ERR("Wrong callback forwarder called\n");
> >
> > diff --git a/dlls/winegstreamer/mfplat.c b/dlls/winegstreamer/mfplat.c
> > index c996f06211e..3667bc3cc38 100644
> > --- a/dlls/winegstreamer/mfplat.c
> > +++ b/dlls/winegstreamer/mfplat.c
> > @@ -16,6 +16,11 @@
> > - Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
> >
> > */
> >
> > +#include "config.h"
> > +#include <gst/gst.h>
> > -
> >
> > +#include "gst_private.h"
> > -
> >
> > #include <stdarg.h>
> >
> > #include "gst_private.h"
> >
> > @@ -436,3 +441,206 @@ HRESULT mfplat_get_class_object(REFCLSID rclsid, REFIID riid, void **obj)
> >   return CLASS_E_CLASSNOTAVAILABLE;
> >
> > }
> > -
> >
> > +const static struct
>
> "static const"

👌
> > +{
> > - const GUID *subtype;
> > - GstVideoFormat format;
> >
> > +}
> > +uncompressed_formats[] =
>
> "uncompressed_video_formats", probably.

👌
> > +{
> > - {&MFVideoFormat_ARGB32,  GST_VIDEO_FORMAT_BGRA},
> > - {&MFVideoFormat_RGB32,   GST_VIDEO_FORMAT_BGRx},
> > - {&MFVideoFormat_RGB24,   GST_VIDEO_FORMAT_BGR},
> > - {&MFVideoFormat_RGB565,  GST_VIDEO_FORMAT_BGR16},
> > - {&MFVideoFormat_RGB555,  GST_VIDEO_FORMAT_BGR15},
> >
> > +};
> > -
> >
> > +/* caps will be modified to represent the exact type needed for the format */
>
> This seems wrong in general.

Why?
> > +static IMFMediaType* transform_to_media_type(GstCaps *caps)
> > +{
> > - IMFMediaType *media_type;
> > - GstStructure *info;
> > - const char *mime_type;
> > -
> > - if (TRACE_ON(mfplat))
> > - {
> > -
> >    gchar *human_readable = gst_caps_to_string(caps);
> > -
> >    TRACE("caps = %s\n", debugstr_a(human_readable));
> > -
> >    g_free(human_readable);
> > - }
> > -
> > - if (FAILED(MFCreateMediaType(&media_type)))
> > - {
> > -
> >    return NULL;
> > - }
> > -
> > - info = gst_caps_get_structure(caps, 0);
> > - mime_type = gst_structure_get_name(info);
> > -
> > - if (!(strncmp(mime_type, "video", 5)))
>
> There's a lot of superfluous parentheses after local not operators in
> this series; this one seems especially superfluous.

👌
> > - {
> > -
> >    GstVideoInfo video_info;
> > -
> > -
> >    if (!(gst_video_info_from_caps(&video_info, caps)))
> > -
> >    {
> > -
> >        return NULL;
> > -
> >    }
> > -
> > -
> >    IMFMediaType_SetGUID(media_type, &MF_MT_MAJOR_TYPE, &MFMediaType_Video);
> > -
> > -
> >    IMFMediaType_SetUINT64(media_type, &MF_MT_FRAME_SIZE, ((UINT64)video_info.width << 32) | video_info.height);
> > -
> > -
> >    IMFMediaType_SetUINT64(media_type, &MF_MT_FRAME_RATE, ((UINT64)video_info.fps_n << 32) | video_info.fps_d);
> > -
> > -
> >    if (!(strcmp(mime_type, "video/x-raw")))
> > -
> >    {
> > -
> >        GUID fourcc_subtype = MFVideoFormat_Base;
> > -
> >        unsigned int i;
> > -
> > -
> >        IMFMediaType_SetUINT32(media_type, &MF_MT_COMPRESSED, FALSE);
> > -
> > -
> >        /* First try FOURCC */
> > -
> >        if ((fourcc_subtype.Data1 = gst_video_format_to_fourcc(video_info.finfo->format)))
> > -
> >        {
> > -
> >            IMFMediaType_SetGUID(media_type, &MF_MT_SUBTYPE, &fourcc_subtype);
> > -
> >        }
> > -
> >        else
> > -
> >        {
> > -
> >            for (i = 0; i < ARRAY_SIZE(uncompressed_formats); i++)
> > -
> >            {
> > -
> >                if (uncompressed_formats[i].format == video_info.finfo->format)
> > -
> >                {
> > -
> >                    IMFMediaType_SetGUID(media_type, &MF_MT_SUBTYPE, uncompressed_formats[i].subtype);
> > -
> >                    break;
> > -
> >                }
> > -
> >            }
> > -
> >            if (i == ARRAY_SIZE(uncompressed_formats))
> > -
> >                FIXME("Unrecognized format.\n");
>
> In which case the function should probably fail.

👌
> > -
> >        }
> > -
> >    }
> > -
> >    else
> > -
> >    {
> > -
> >        FIXME("Unrecognized video format %s\n", mime_type);
> > -
> >        IMFMediaType_Release(media_type);
> > -
> >        return NULL;
> > -
> >    }
> > - }
> > - else if (!(strncmp(mime_type, "audio", 5)))
> > - {
> > -
> >    gint rate, channels, bitrate;
> > -
> >    guint64 channel_mask;
> > -
> >    IMFMediaType_SetGUID(media_type, &MF_MT_MAJOR_TYPE, &MFMediaType_Audio);
> > -
> > -
> >    if (gst_structure_get_int(info, "rate", &rate))
> > -
> >        IMFMediaType_SetUINT32(media_type, &MF_MT_AUDIO_SAMPLES_PER_SECOND, rate);
> > -
> > -
> >    if (gst_structure_get_int(info, "channels", &channels))
> > -
> >        IMFMediaType_SetUINT32(media_type, &MF_MT_AUDIO_NUM_CHANNELS, channels);
> > -
> > -
> >    if (gst_structure_get(info, "channel-mask", GST_TYPE_BITMASK, &channel_mask, NULL))
> > -
> >        IMFMediaType_SetUINT32(media_type, &MF_MT_AUDIO_CHANNEL_MASK, (DWORD)channel_mask);
>
> Superfluous cast.

👌
> > -
> > -
> >    if (gst_structure_get_int(info, "bitrate", &bitrate))
> > -
> >        IMFMediaType_SetUINT32(media_type, &MF_MT_AVG_BITRATE, bitrate);
> > -
> > -
> >    if (!(strcmp(mime_type, "audio/x-raw")))
> > -
> >    {
> > -
> >        const char *format;
> > -
> >        if ((format = gst_structure_get_string(info, "format")))
>
> You may find it easier to use gst_audio_info_from_caps() here.

Does this work on compressed audio types as well?
> > -
> >        {
> > -
> >            char type;
> > -
> >            unsigned int bits_per_sample;
> > -
> >            char endian[2];
> > -
> >            char new_format[6];
> > -
> >            if ((strlen(format) > 5) || (sscanf(format, "%c%u%2c", &type, &bits_per_sample, endian) < 2))
> > -
> >            {
> > -
> >                FIXME("Unhandled audio format %s\n", format);
> > -
> >                IMFMediaType_Release(media_type);
> > -
> >                return NULL;
> > -
> >            }
> > -
> > -
> >            if (type == 'F')
> > -
> >            {
> > -
> >                IMFMediaType_SetGUID(media_type, &MF_MT_SUBTYPE, &MFAudioFormat_Float);
> > -
> >            }
> > -
> >            else if (type == 'U' || type == 'S')
> > -
> >            {
> > -
> >                IMFMediaType_SetGUID(media_type, &MF_MT_SUBTYPE, &MFAudioFormat_PCM);
> > -
> >                if (bits_per_sample == 8)
> > -
> >                    type = 'U';
> > -
> >                else
> > -
> >                    type = 'S';
> > -
> >            }
> > -
> >            else
> > -
> >            {
> > -
> >                FIXME("Unrecognized audio format: %s\n", format);
> > -
> >                IMFMediaType_Release(media_type);
> > -
> >                return NULL;
> > -
> >            }
> > -
> > -
> >            IMFMediaType_SetUINT32(media_type, &MF_MT_AUDIO_BITS_PER_SAMPLE, bits_per_sample);
> > -
> > -
> >            if (endian[0] == 'B')
> > -
> >                endian[0] = 'L';
> > -
> > -
> >            sprintf(new_format, "%c%u%.2s", type, bits_per_sample, bits_per_sample > 8 ? endian : 0);
> > -
> >            gst_caps_set_simple(caps, "format", G_TYPE_STRING, new_format, NULL);
> > -
> >        }
> > -
> >        else
> > -
> >        {
> > -
> >            ERR("Failed to get audio format\n");
> > -
> >        }
> > -
> >    }
> > -
> >    else
> > -
> >    {
> > -
> >        FIXME("Unrecognized audio format %s\n", mime_type);
> > -
> >        IMFMediaType_Release(media_type);
> > -
> >        return NULL;
> > -
> >    }
> > - }
> > - else
> > - {
> > -
> >    IMFMediaType_Release(media_type);
> > -
> >    return NULL;
> > - }
> > -
> > - return media_type;
> >
> > +}
> > -
> >
> > +/* returns NULL if doesn't match exactly */
> > +IMFMediaType *mf_media_type_from_caps(GstCaps *caps)
> > +{
> > - GstCaps *writeable_caps;
> > - IMFMediaType *ret;
> > -
> > - writeable_caps = gst_caps_copy(caps);
> > - ret = transform_to_media_type(writeable_caps);
> > -
> > - if (!(gst_caps_is_equal(caps, writeable_caps)))
> > - {
> > -
> >    IMFMediaType_Release(ret);
> > -
> >    ret = NULL;
> > - }
> > - gst_caps_unref(writeable_caps);
> > - return ret;
> >
> > +}
> > -
> >
> > +GstCaps *make_mf_compatible_caps(GstCaps *caps)
> > +{
> > - GstCaps *ret;
> > - IMFMediaType *media_type;
> > -
> > - ret = gst_caps_copy(caps);
> > -
> > - if ((media_type = transform_to_media_type(ret)))
> > -
> >    IMFMediaType_Release(media_type);
> > -
> > - if (!media_type)
> > - {
> > -
> >    gst_caps_unref(ret);
> > -
> >    return NULL;
> > - }
> > -
> > - return ret;
> >
> > +}