Added filter ParseSegment()

filter.go

@@ -2,7 +2,9 @@ package astiav
 
 //#include <libavfilter/avfilter.h>
 import "C"
-import "unsafe"
+import (
+	"unsafe"
+)
 
 // https://github.com/FFmpeg/FFmpeg/blob/n5.0/libavfilter/avfilter.h#L165
 type Filter struct {
@@ -29,3 +31,25 @@ func (f *Filter) Name() string {
 func (f *Filter) String() string {
 	return f.Name()
 }
+
+func (f *Filter) NbInputs() int {
+	return int(f.c.nb_inputs)
+}
+
+func (f *Filter) NbOutputs() int {
+	return int(f.c.nb_outputs)
+}
+
+func (f *Filter) Inputs() (ps []*FilterPad) {
+	for idx := 0; idx < f.NbInputs(); idx++ {
+		ps = append(ps, newFilterPad(MediaType(C.avfilter_pad_get_type(f.c.inputs, C.int(idx)))))
+	}
+	return
+}
+
+func (f *Filter) Outputs() (ps []*FilterPad) {
+	for idx := 0; idx < f.NbOutputs(); idx++ {
+		ps = append(ps, newFilterPad(MediaType(C.avfilter_pad_get_type(f.c.outputs, C.int(idx)))))
+	}
+	return
+}

filter_chain.go

@@ -0,0 +1,32 @@
+package astiav
+
+//#include <libavfilter/avfilter.h>
+import "C"
+import (
+	"math"
+	"unsafe"
+)
+
+// https://github.com/FFmpeg/FFmpeg/blob/n7.0/libavfilter/avfilter.h#L1142
+type FilterChain struct {
+	c *C.AVFilterChain
+}
+
+func newFilterChainFromC(c *C.AVFilterChain) *FilterChain {
+	if c == nil {
+		return nil
+	}
+	return &FilterChain{c: c}
+}
+
+func (fc *FilterChain) Filters() (fs []*FilterParams) {
+	fcs := (*[(math.MaxInt32 - 1) / unsafe.Sizeof((*C.AVFilterParams)(nil))](*C.AVFilterParams))(unsafe.Pointer(fc.c.filters))
+	for i := 0; i < fc.NbFilters(); i++ {
+		fs = append(fs, newFilterParamsFromC(fcs[i]))
+	}
+	return
+}
+
+func (fc *FilterChain) NbFilters() int {
+	return int(fc.c.nb_filters)
+}

filter_graph.go

@@ -97,6 +97,16 @@ func (g *FilterGraph) Parse(content string, inputs, outputs *FilterInOut) error
 	return newError(C.avfilter_graph_parse_ptr(g.c, cc, ic, oc, nil))
 }
 
+func (g *FilterGraph) ParseSegment(content string) (*FilterGraphSegment, error) {
+	cc := C.CString(content)
+	defer C.free(unsafe.Pointer(cc))
+	var cs *C.AVFilterGraphSegment
+	if err := newError(C.avfilter_graph_segment_parse(g.c, cc, 0, &cs)); err != nil {
+		return nil, err
+	}
+	return newFilterGraphSegmentFromC(cs), nil
+}
+
 func (g *FilterGraph) Configure() error {
 	return newError(C.avfilter_graph_config(g.c, nil))
 }

filter_graph_segment.go

@@ -0,0 +1,36 @@
+package astiav
+
+//#include <libavfilter/avfilter.h>
+import "C"
+import (
+	"math"
+	"unsafe"
+)
+
+// https://github.com/FFmpeg/FFmpeg/blob/n7.0/libavfilter/avfilter.h#L1156
+type FilterGraphSegment struct {
+	c *C.AVFilterGraphSegment
+}
+
+func newFilterGraphSegmentFromC(c *C.AVFilterGraphSegment) *FilterGraphSegment {
+	if c == nil {
+		return nil
+	}
+	return &FilterGraphSegment{c: c}
+}
+
+func (fgs *FilterGraphSegment) Free() {
+	C.avfilter_graph_segment_free(&fgs.c)
+}
+
+func (fgs *FilterGraphSegment) Chains() (cs []*FilterChain) {
+	ccs := (*[(math.MaxInt32 - 1) / unsafe.Sizeof((*C.AVFilterChain)(nil))](*C.AVFilterChain))(unsafe.Pointer(fgs.c.chains))
+	for i := 0; i < fgs.NbChains(); i++ {
+		cs = append(cs, newFilterChainFromC(ccs[i]))
+	}
+	return
+}
+
+func (fgs *FilterGraphSegment) NbChains() int {
+	return int(fgs.c.nb_chains)
+}

filter_graph_test.go

@@ -97,13 +97,13 @@ func TestFilterGraph(t *testing.T) {
 				channelLayout: ChannelLayoutStereo,
 				mediaType:     MediaTypeAudio,
 				sampleFormat:  SampleFormatS16,
-				sampleRate:    4,
+				sampleRate:    3,
 				timeBase:      NewRational(1, 4),
 			},
 			buffersinkName: "abuffersink",
 			buffersrcName:  "abuffer",
-			content:        "[input_1]aformat=sample_fmts=s16:channel_layouts=stereo:sample_rates=4,asettb=1/4",
-			s:              "                                                  +---------------+\nParsed_asettb_1:default--[4Hz s16:stereo]--default|  filter_out   |\n                                                  | (abuffersink) |\n                                                  +---------------+\n\n+-------------+\n| filter_in_1 |default--[2Hz fltp:mono]--auto_aresample_0:default\n|  (abuffer)  |\n+-------------+\n\n                                                   +------------------+\nauto_aresample_0:default--[4Hz s16:stereo]--default| Parsed_aformat_0 |default--[4Hz s16:stereo]--Parsed_asettb_1:default\n                                                   |    (aformat)     |\n                                                   +------------------+\n\n                                                   +-----------------+\nParsed_aformat_0:default--[4Hz s16:stereo]--default| Parsed_asettb_1 |default--[4Hz s16:stereo]--filter_out:default\n                                                   |    (asettb)     |\n                                                   +-----------------+\n\n                                             +------------------+\nfilter_in_1:default--[2Hz fltp:mono]--default| auto_aresample_0 |default--[4Hz s16:stereo]--Parsed_aformat_0:default\n                                             |   (aresample)    |\n                                             +------------------+\n\n",
+			content:        "[input_1]aformat=sample_fmts=s16:channel_layouts=stereo:sample_rates=3,asettb=1/4",
+			s:              "                                                  +---------------+\nParsed_asettb_1:default--[3Hz s16:stereo]--default|  filter_out   |\n                                                  | (abuffersink) |\n                                                  +---------------+\n\n+-------------+\n| filter_in_1 |default--[2Hz fltp:mono]--auto_aresample_0:default\n|  (abuffer)  |\n+-------------+\n\n                                                   +------------------+\nauto_aresample_0:default--[3Hz s16:stereo]--default| Parsed_aformat_0 |default--[3Hz s16:stereo]--Parsed_asettb_1:default\n                                                   |    (aformat)     |\n                                                   +------------------+\n\n                                                   +-----------------+\nParsed_aformat_0:default--[3Hz s16:stereo]--default| Parsed_asettb_1 |default--[3Hz s16:stereo]--filter_out:default\n                                                   |    (asettb)     |\n                                                   +-----------------+\n\n                                             +------------------+\nfilter_in_1:default--[2Hz fltp:mono]--default| auto_aresample_0 |default--[3Hz s16:stereo]--Parsed_aformat_0:default\n                                             |   (aresample)    |\n                                             +------------------+\n\n",
 			sources: []FilterArgs{
 				{
 					"channel_layout": ChannelLayoutMono.String(),
@@ -201,6 +201,26 @@ func TestFilterGraph(t *testing.T) {
 		}
 	}
 
+	fg2 := AllocFilterGraph()
+	require.NotNil(t, fg2)
+	defer fg2.Free()
+	fgs, err := fg2.ParseSegment("anullsrc")
+	require.NoError(t, err)
+	defer fgs.Free()
+	require.Equal(t, 1, fgs.NbChains())
+	cs := fgs.Chains()
+	require.Equal(t, 1, len(cs))
+	require.Equal(t, 1, cs[0].NbFilters())
+	fs := cs[0].Filters()
+	require.Equal(t, 1, len(fs))
+	f := FindFilterByName(fs[0].FilterName())
+	require.NotNil(t, f)
+	require.Equal(t, 0, f.NbInputs())
+	require.Equal(t, 1, f.NbOutputs())
+	os := f.Outputs()
+	require.Equal(t, 1, len(os))
+	require.Equal(t, MediaTypeAudio, os[0].MediaType())
+
 	// TODO Test BuffersrcAddFrame
 	// TODO Test BuffersinkGetFrame
 }

filter_pad.go

@@ -0,0 +1,14 @@
+package astiav
+
+// Struct attributes are internal but there are C functions to get some of them
+type FilterPad struct {
+	mediaType MediaType
+}
+
+func newFilterPad(mediaType MediaType) *FilterPad {
+	return &FilterPad{mediaType: mediaType}
+}
+
+func (fp *FilterPad) MediaType() MediaType {
+	return fp.mediaType
+}

filter_params.go

@@ -0,0 +1,20 @@
+package astiav
+
+//#include <libavfilter/avfilter.h>
+import "C"
+
+// https://github.com/FFmpeg/FFmpeg/blob/n7.0/libavfilter/avfilter.h#L1075
+type FilterParams struct {
+	c *C.AVFilterParams
+}
+
+func newFilterParamsFromC(c *C.AVFilterParams) *FilterParams {
+	if c == nil {
+		return nil
+	}
+	return &FilterParams{c: c}
+}
+
+func (fp *FilterParams) FilterName() string {
+	return C.GoString(fp.c.filter_name)
+}