Removed args from NewXXXFilterContext()

BREAKING_CHANGES.md

@@ -1,3 +1,8 @@
+# v0.29.0
+
+- `NewFilterContext` has been removed, use `NewBuffersinkFilterContext` or `NewBuffersrcFilterContext` instead 
+- `args` has been removed from `NewBuffersinkFilterContext` and `NewBuffersrcFilterContext`. Instead, after calling `NewBuffersrcFilterContext`, you need to use `BuffersrcFilterContext`.`SetParameters` then `BuffersrcFilterContext`.`Initialize`. You don't need to use anything else after calling `NewBuffersinkFilterContext`
+
 # v0.27.0
 
 - make sure to call the `IOInterrupter`.`Free` method after using `NewIOInterrupter`

buffersrc_filter_context.go

@@ -24,6 +24,11 @@ func (bfc *BuffersrcFilterContext) FilterContext() *FilterContext {
 	return bfc.fc
 }
 
+// https://ffmpeg.org/doxygen/7.0/group__lavfi.html#ga8c15af28902395399fe455f6f8236848
+func (bfc *BuffersrcFilterContext) Initialize() error {
+	return newError(C.avfilter_init_dict(bfc.fc.c, nil))
+}
+
 // https://ffmpeg.org/doxygen/7.0/group__lavfi__buffersrc.html#ga398cd2a84f8b4a588197ab9d90135048
 func (bfc *BuffersrcFilterContext) SetParameters(bfcp *BuffersrcFilterContextParameters) error {
 	return newError(C.av_buffersrc_parameters_set(bfc.fc.c, bfcp.c))

buffersrc_filter_context_parameters.go

@@ -30,6 +30,47 @@ func (bfcp *BuffersrcFilterContextParameters) Free() {
 	}
 }
 
+// https://ffmpeg.org/doxygen/7.0/structAVBufferSrcParameters.html#a5267368bf88b4f2a65a5e06ac3f9ecd4
+func (bfcp *BuffersrcFilterContextParameters) ChannelLayout() ChannelLayout {
+	l, _ := newChannelLayoutFromC(&bfcp.c.ch_layout).clone()
+	return l
+}
+
+// https://ffmpeg.org/doxygen/7.0/structAVBufferSrcParameters.html#a5267368bf88b4f2a65a5e06ac3f9ecd4
+func (bfcp *BuffersrcFilterContextParameters) SetChannelLayout(l ChannelLayout) {
+	l.copy(&bfcp.c.ch_layout) //nolint: errcheck
+}
+
+// https://ffmpeg.org/doxygen/7.0/structAVBufferSrcParameters.html#a442add2b039f416dd7c92ccf1ccd0d3b
+func (bfcp *BuffersrcFilterContextParameters) ColorRange() ColorRange {
+	return ColorRange(bfcp.c.color_range)
+}
+
+// https://ffmpeg.org/doxygen/7.0/structAVBufferSrcParameters.html#a442add2b039f416dd7c92ccf1ccd0d3b
+func (bfcp *BuffersrcFilterContextParameters) SetColorRange(r ColorRange) {
+	bfcp.c.color_range = C.enum_AVColorRange(r)
+}
+
+// https://ffmpeg.org/doxygen/7.0/structAVBufferSrcParameters.html#a700226626af70f787c930d7506554757
+func (bfcp *BuffersrcFilterContextParameters) ColorSpace() ColorSpace {
+	return ColorSpace(bfcp.c.color_space)
+}
+
+// https://ffmpeg.org/doxygen/7.0/structAVBufferSrcParameters.html#a700226626af70f787c930d7506554757
+func (bfcp *BuffersrcFilterContextParameters) SetColorSpace(s ColorSpace) {
+	bfcp.c.color_space = C.enum_AVColorSpace(s)
+}
+
+// https://ffmpeg.org/doxygen/7.0/structAVBufferSrcParameters.html#a032a202496206e18449c66233058647a
+func (bfcp *BuffersrcFilterContextParameters) Framerate() Rational {
+	return newRationalFromC(bfcp.c.frame_rate)
+}
+
+// https://ffmpeg.org/doxygen/7.0/structAVBufferSrcParameters.html#a032a202496206e18449c66233058647a
+func (bfcp *BuffersrcFilterContextParameters) SetFramerate(f Rational) {
+	bfcp.c.frame_rate = f.c
+}
+
 // https://ffmpeg.org/doxygen/7.0/structAVBufferSrcParameters.html#a86c49b4202433037c9e2b0b6ae541534
 func (bfcp *BuffersrcFilterContextParameters) SetHardwareFrameContext(hfc *HardwareFrameContext) {
 	if bfcp.c.hw_frames_ctx != nil {
@@ -41,3 +82,73 @@ func (bfcp *BuffersrcFilterContextParameters) SetHardwareFrameContext(hfc *Hardw
 		bfcp.c.hw_frames_ctx = nil
 	}
 }
+
+// https://ffmpeg.org/doxygen/7.0/structAVBufferSrcParameters.html#a89783d603b84908fb1998bbbea981b70
+func (bfcp *BuffersrcFilterContextParameters) Height() int {
+	return int(bfcp.c.height)
+}
+
+// https://ffmpeg.org/doxygen/7.0/structAVBufferSrcParameters.html#a89783d603b84908fb1998bbbea981b70
+func (bfcp *BuffersrcFilterContextParameters) SetHeight(height int) {
+	bfcp.c.height = C.int(height)
+}
+
+// https://ffmpeg.org/doxygen/7.0/structAVBufferSrcParameters.html#a56f28f81f1a86cecc39a8d61674912b8
+func (bfcp *BuffersrcFilterContextParameters) PixelFormat() PixelFormat {
+	return PixelFormat(bfcp.c.format)
+}
+
+// https://ffmpeg.org/doxygen/7.0/structAVBufferSrcParameters.html#a56f28f81f1a86cecc39a8d61674912b8
+func (bfcp *BuffersrcFilterContextParameters) SetPixelFormat(f PixelFormat) {
+	bfcp.c.format = C.int(f)
+}
+
+// https://ffmpeg.org/doxygen/7.0/structAVBufferSrcParameters.html#ae47c141ea7a7770351613242229f951a
+func (bfcp *BuffersrcFilterContextParameters) SampleAspectRatio() Rational {
+	return newRationalFromC(bfcp.c.sample_aspect_ratio)
+}
+
+// https://ffmpeg.org/doxygen/7.0/structAVBufferSrcParameters.html#ae47c141ea7a7770351613242229f951a
+func (bfcp *BuffersrcFilterContextParameters) SetSampleAspectRatio(r Rational) {
+	bfcp.c.sample_aspect_ratio = r.c
+}
+
+// https://ffmpeg.org/doxygen/7.0/structAVBufferSrcParameters.html#a56f28f81f1a86cecc39a8d61674912b8
+func (bfcp *BuffersrcFilterContextParameters) SampleFormat() SampleFormat {
+	return SampleFormat(bfcp.c.format)
+}
+
+// https://ffmpeg.org/doxygen/7.0/structAVBufferSrcParameters.html#a56f28f81f1a86cecc39a8d61674912b8
+func (bfcp *BuffersrcFilterContextParameters) SetSampleFormat(f SampleFormat) {
+	bfcp.c.format = C.int(f)
+}
+
+// https://ffmpeg.org/doxygen/7.0/structAVBufferSrcParameters.html#a34a1613f1e80f8520c159fac59e29834
+func (bfcp *BuffersrcFilterContextParameters) SampleRate() int {
+	return int(bfcp.c.sample_rate)
+}
+
+// https://ffmpeg.org/doxygen/7.0/structAVBufferSrcParameters.html#a34a1613f1e80f8520c159fac59e29834
+func (bfcp *BuffersrcFilterContextParameters) SetSampleRate(sampleRate int) {
+	bfcp.c.sample_rate = C.int(sampleRate)
+}
+
+// https://ffmpeg.org/doxygen/7.0/structAVBufferSrcParameters.html#a7767325c1259942a33586f05c90e38b0
+func (bfcp *BuffersrcFilterContextParameters) TimeBase() Rational {
+	return newRationalFromC(bfcp.c.time_base)
+}
+
+// https://ffmpeg.org/doxygen/7.0/structAVBufferSrcParameters.html#a7767325c1259942a33586f05c90e38b0
+func (bfcp *BuffersrcFilterContextParameters) SetTimeBase(r Rational) {
+	bfcp.c.time_base = r.c
+}
+
+// https://ffmpeg.org/doxygen/7.0/structAVBufferSrcParameters.html#a6c6f3d9ed8b427070e9055e7ac61263f
+func (bfcp *BuffersrcFilterContextParameters) Width() int {
+	return int(bfcp.c.width)
+}
+
+// https://ffmpeg.org/doxygen/7.0/structAVBufferSrcParameters.html#a6c6f3d9ed8b427070e9055e7ac61263f
+func (bfcp *BuffersrcFilterContextParameters) SetWidth(width int) {
+	bfcp.c.width = C.int(width)
+}

buffersrc_filter_context_parameters_test.go

@@ -0,0 +1,34 @@
+package astiav
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestBuffersrcFilterContextParameters(t *testing.T) {
+	p := AllocBuffersrcFilterContextParameters()
+	defer p.Free()
+	p.SetChannelLayout(ChannelLayoutStereo)
+	require.Equal(t, ChannelLayoutStereo, p.ChannelLayout())
+	p.SetColorRange(ColorRangeMpeg)
+	require.Equal(t, ColorRangeMpeg, p.ColorRange())
+	p.SetColorSpace(ColorSpaceBt470Bg)
+	require.Equal(t, ColorSpaceBt470Bg, p.ColorSpace())
+	p.SetFramerate(NewRational(1, 2))
+	require.Equal(t, NewRational(1, 2), p.Framerate())
+	p.SetHeight(1)
+	require.Equal(t, 1, p.Height())
+	p.SetPixelFormat(PixelFormatRgba)
+	require.Equal(t, PixelFormatRgba, p.PixelFormat())
+	p.SetSampleAspectRatio(NewRational(3, 4))
+	require.Equal(t, NewRational(3, 4), p.SampleAspectRatio())
+	p.SetSampleFormat(SampleFormatDblp)
+	require.Equal(t, SampleFormatDblp, p.SampleFormat())
+	p.SetSampleRate(2)
+	require.Equal(t, 2, p.SampleRate())
+	p.SetTimeBase(NewRational(5, 6))
+	require.Equal(t, NewRational(5, 6), p.TimeBase())
+	p.SetWidth(3)
+	require.Equal(t, 3, p.Width())
+}

class_test.go

@@ -40,9 +40,9 @@ func TestClassers(t *testing.T) {
 	require.NotNil(t, cc)
 	bufferSink := FindFilterByName("buffersink")
 	require.NotNil(t, bufferSink)
-	fc1, err := f1.NewFilterContext(bufferSink, "filter_out", nil)
+	bfc1, err := f1.NewBuffersinkFilterContext(bufferSink, "filter_out")
 	require.NoError(t, err)
-	_, err = f2.NewFilterContext(bufferSink, "filter_out", nil)
+	_, err = f2.NewBuffersinkFilterContext(bufferSink, "filter_out")
 	require.NoError(t, err)
 	fmc1 := AllocFormatContext()
 	fmc2 := AllocFormatContext()
@@ -64,7 +64,7 @@ func TestClassers(t *testing.T) {
 
 	bfc.Free()
 	cc.Free()
-	fc1.Free()
+	bfc1.FilterContext().Free()
 	f1.Free()
 	f2.Free()
 	fmc1.Free()

examples/filtering/main.go

@@ -5,7 +5,6 @@ import (
 	"flag"
 	"fmt"
 	"log"
-	"strconv"
 	"strings"
 
 	"github.com/asticode/go-astiav"
@@ -250,20 +249,36 @@ func initFilter() (err error) {
 	}
 
 	// Create filter contexts
-	if s.buffersrcContext, err = s.filterGraph.NewBuffersrcFilterContext(buffersrc, "in", astiav.FilterArgs{
-		"pix_fmt":      strconv.Itoa(int(s.decCodecContext.PixelFormat())),
-		"pixel_aspect": s.decCodecContext.SampleAspectRatio().String(),
-		"time_base":    s.inputStream.TimeBase().String(),
-		"video_size":   strconv.Itoa(s.decCodecContext.Width()) + "x" + strconv.Itoa(s.decCodecContext.Height()),
-	}); err != nil {
+	if s.buffersrcContext, err = s.filterGraph.NewBuffersrcFilterContext(buffersrc, "in"); err != nil {
 		err = fmt.Errorf("main: creating buffersrc context failed: %w", err)
 		return
 	}
-	if s.buffersinkContext, err = s.filterGraph.NewBuffersinkFilterContext(buffersink, "in", nil); err != nil {
+	if s.buffersinkContext, err = s.filterGraph.NewBuffersinkFilterContext(buffersink, "in"); err != nil {
 		err = fmt.Errorf("main: creating buffersink context failed: %w", err)
 		return
 	}
 
+	// Create buffersrc context parameters
+	buffersrcContextParameters := astiav.AllocBuffersrcFilterContextParameters()
+	defer buffersrcContextParameters.Free()
+	buffersrcContextParameters.SetHeight(s.decCodecContext.Height())
+	buffersrcContextParameters.SetPixelFormat(s.decCodecContext.PixelFormat())
+	buffersrcContextParameters.SetSampleAspectRatio(s.decCodecContext.SampleAspectRatio())
+	buffersrcContextParameters.SetTimeBase(s.inputStream.TimeBase())
+	buffersrcContextParameters.SetWidth(s.decCodecContext.Width())
+
+	// Set buffersrc context parameters
+	if err = s.buffersrcContext.SetParameters(buffersrcContextParameters); err != nil {
+		err = fmt.Errorf("main: setting buffersrc context parameters failed: %w", err)
+		return
+	}
+
+	// Initialize buffersrc context
+	if err = s.buffersrcContext.Initialize(); err != nil {
+		err = fmt.Errorf("main: initializing buffersrc context failed: %w", err)
+		return
+	}
+
 	// Update outputs
 	outputs.SetName("in")
 	outputs.SetFilterContext(s.buffersrcContext.FilterContext())

examples/hardware_decoding_filtering/main.go

@@ -5,7 +5,6 @@ import (
 	"flag"
 	"fmt"
 	"log"
-	"strconv"
 	"strings"
 
 	"github.com/asticode/go-astiav"
@@ -294,28 +293,34 @@ func initFilter() (err error) {
 	}
 
 	// Create filter contexts
-	if buffersrcContext, err = filterGraph.NewBuffersrcFilterContext(buffersrc, "in", astiav.FilterArgs{
-		"pix_fmt":      strconv.Itoa(int(decCodecContext.PixelFormat())),
-		"pixel_aspect": decCodecContext.SampleAspectRatio().String(),
-		"time_base":    inputStream.TimeBase().String(),
-		"video_size":   strconv.Itoa(decCodecContext.Width()) + "x" + strconv.Itoa(decCodecContext.Height()),
-	}); err != nil {
+	if buffersrcContext, err = filterGraph.NewBuffersrcFilterContext(buffersrc, "in"); err != nil {
 		err = fmt.Errorf("main: creating buffersrc context failed: %w", err)
 		return
 	}
-	if buffersinkContext, err = filterGraph.NewBuffersinkFilterContext(buffersink, "in", nil); err != nil {
+	if buffersinkContext, err = filterGraph.NewBuffersinkFilterContext(buffersink, "in"); err != nil {
 		err = fmt.Errorf("main: creating buffersink context failed: %w", err)
 		return
 	}
 
-	// Create buffersrc parameters
-	bfcp := astiav.AllocBuffersrcFilterContextParameters()
-	defer bfcp.Free()
-	bfcp.SetHardwareFrameContext(decCodecContext.HardwareFrameContext())
+	// Create buffersrc context parameters
+	buffersrcContextParameters := astiav.AllocBuffersrcFilterContextParameters()
+	defer buffersrcContextParameters.Free()
+	buffersrcContextParameters.SetHardwareFrameContext(decCodecContext.HardwareFrameContext())
+	buffersrcContextParameters.SetHeight(decCodecContext.Height())
+	buffersrcContextParameters.SetPixelFormat(decCodecContext.PixelFormat())
+	buffersrcContextParameters.SetSampleAspectRatio(decCodecContext.SampleAspectRatio())
+	buffersrcContextParameters.SetTimeBase(inputStream.TimeBase())
+	buffersrcContextParameters.SetWidth(decCodecContext.Width())
 
-	// Set buffersrc parameters
-	if err = buffersrcContext.SetParameters(bfcp); err != nil {
-		err = fmt.Errorf("main: setting buffersrc parameters failed: %w", err)
+	// Set buffersrc context parameters
+	if err = buffersrcContext.SetParameters(buffersrcContextParameters); err != nil {
+		err = fmt.Errorf("main: setting buffersrc context parameters failed: %w", err)
+		return
+	}
+
+	// Initialize buffersrc context
+	if err = buffersrcContext.Initialize(); err != nil {
+		err = fmt.Errorf("main: initializing buffersrc context failed: %w", err)
 		return
 	}
 

examples/transcoding/main.go

@@ -5,7 +5,6 @@ import (
 	"flag"
 	"fmt"
 	"log"
-	"strconv"
 	"strings"
 
 	"github.com/asticode/go-astiav"
@@ -378,29 +377,29 @@ func initFilters() (err error) {
 		}
 		c.Add(inputs.Free)
 
+		// Create buffersrc context parameters
+		buffersrcContextParameters := astiav.AllocBuffersrcFilterContextParameters()
+		defer buffersrcContextParameters.Free()
+
 		// Switch on media type
-		var args astiav.FilterArgs
 		var buffersrc, buffersink *astiav.Filter
 		var content string
 		switch s.decCodecContext.MediaType() {
 		case astiav.MediaTypeAudio:
-			args = astiav.FilterArgs{
-				"channel_layout": s.decCodecContext.ChannelLayout().String(),
-				"sample_fmt":     s.decCodecContext.SampleFormat().Name(),
-				"sample_rate":    strconv.Itoa(s.decCodecContext.SampleRate()),
-				"time_base":      s.decCodecContext.TimeBase().String(),
-			}
 			buffersrc = astiav.FindFilterByName("abuffer")
+			buffersrcContextParameters.SetChannelLayout(s.decCodecContext.ChannelLayout())
+			buffersrcContextParameters.SetSampleFormat(s.decCodecContext.SampleFormat())
+			buffersrcContextParameters.SetSampleRate(s.decCodecContext.SampleRate())
+			buffersrcContextParameters.SetTimeBase(s.decCodecContext.TimeBase())
 			buffersink = astiav.FindFilterByName("abuffersink")
 			content = fmt.Sprintf("aformat=sample_fmts=%s:channel_layouts=%s", s.encCodecContext.SampleFormat().Name(), s.encCodecContext.ChannelLayout().String())
 		default:
-			args = astiav.FilterArgs{
-				"pix_fmt":      strconv.Itoa(int(s.decCodecContext.PixelFormat())),
-				"pixel_aspect": s.decCodecContext.SampleAspectRatio().String(),
-				"time_base":    s.inputStream.TimeBase().String(),
-				"video_size":   strconv.Itoa(s.decCodecContext.Width()) + "x" + strconv.Itoa(s.decCodecContext.Height()),
-			}
 			buffersrc = astiav.FindFilterByName("buffer")
+			buffersrcContextParameters.SetHeight(s.decCodecContext.Height())
+			buffersrcContextParameters.SetPixelFormat(s.decCodecContext.PixelFormat())
+			buffersrcContextParameters.SetSampleAspectRatio(s.decCodecContext.SampleAspectRatio())
+			buffersrcContextParameters.SetTimeBase(s.inputStream.TimeBase())
+			buffersrcContextParameters.SetWidth(s.decCodecContext.Width())
 			buffersink = astiav.FindFilterByName("buffersink")
 			content = fmt.Sprintf("format=pix_fmts=%s", s.encCodecContext.PixelFormat().Name())
 		}
@@ -416,15 +415,27 @@ func initFilters() (err error) {
 		}
 
 		// Create filter contexts
-		if s.buffersrcContext, err = s.filterGraph.NewBuffersrcFilterContext(buffersrc, "in", args); err != nil {
+		if s.buffersrcContext, err = s.filterGraph.NewBuffersrcFilterContext(buffersrc, "in"); err != nil {
 			err = fmt.Errorf("main: creating buffersrc context failed: %w", err)
 			return
 		}
-		if s.buffersinkContext, err = s.filterGraph.NewBuffersinkFilterContext(buffersink, "out", nil); err != nil {
+		if s.buffersinkContext, err = s.filterGraph.NewBuffersinkFilterContext(buffersink, "out"); err != nil {
 			err = fmt.Errorf("main: creating buffersink context failed: %w", err)
 			return
 		}
 
+		// Set buffersrc context parameters
+		if err = s.buffersrcContext.SetParameters(buffersrcContextParameters); err != nil {
+			err = fmt.Errorf("main: setting buffersrc context parameters failed: %w", err)
+			return
+		}
+
+		// Initialize buffersrc context
+		if err = s.buffersrcContext.Initialize(); err != nil {
+			err = fmt.Errorf("main: initializing buffersrc context failed: %w", err)
+			return
+		}
+
 		// Update outputs
 		outputs.SetName("in")
 		outputs.SetFilterContext(s.buffersrcContext.FilterContext())

filter_graph.go

@@ -3,7 +3,7 @@ package astiav
 //#include <libavfilter/avfilter.h>
 import "C"
 import (
-	"strings"
+	"errors"
 	"unsafe"
 )
 
@@ -84,47 +84,29 @@ func (g *FilterGraph) SetThreadType(t ThreadType) {
 	g.c.thread_type = C.int(t)
 }
 
-type FilterArgs map[string]string
-
-func (args FilterArgs) String() string {
-	var ss []string
-	for k, v := range args {
-		ss = append(ss, k+"="+v)
-	}
-	return strings.Join(ss, ":")
-}
-
 // https://ffmpeg.org/doxygen/7.0/group__lavfi.html#gac0788a9ab6966dba9318b5d5c7524fea
-func (g *FilterGraph) NewFilterContext(f *Filter, name string, args FilterArgs) (*FilterContext, error) {
-	ca := (*C.char)(nil)
-	if len(args) > 0 {
-		ca = C.CString(args.String())
-		defer C.free(unsafe.Pointer(ca))
-	}
-	cn := C.CString(name)
-	defer C.free(unsafe.Pointer(cn))
+func (g *FilterGraph) NewBuffersinkFilterContext(f *Filter, name string) (*BuffersinkFilterContext, error) {
+	cname := C.CString(name)
+	defer C.free(unsafe.Pointer(cname))
 	var c *C.AVFilterContext
-	if err := newError(C.avfilter_graph_create_filter(&c, f.c, cn, ca, nil, g.c)); err != nil {
+	if err := newError(C.avfilter_graph_create_filter(&c, f.c, cname, nil, nil, g.c)); err != nil {
 		return nil, err
 	}
 	fc := newFilterContext(c)
 	g.fcs = append(g.fcs, fc)
-	return fc, nil
-}
-
-func (g *FilterGraph) NewBuffersinkFilterContext(f *Filter, name string, args FilterArgs) (*BuffersinkFilterContext, error) {
-	fc, err := g.NewFilterContext(f, name, args)
-	if err != nil {
-		return nil, err
-	}
 	return newBuffersinkFilterContext(fc), nil
 }
 
-func (g *FilterGraph) NewBuffersrcFilterContext(f *Filter, name string, args FilterArgs) (*BuffersrcFilterContext, error) {
-	fc, err := g.NewFilterContext(f, name, args)
-	if err != nil {
-		return nil, err
+// https://ffmpeg.org/doxygen/7.0/group__lavfi.html#gaa9af17ecf4c5c87307b57cf08411088b
+func (g *FilterGraph) NewBuffersrcFilterContext(f *Filter, name string) (*BuffersrcFilterContext, error) {
+	cname := C.CString(name)
+	defer C.free(unsafe.Pointer(cname))
+	c := C.avfilter_graph_alloc_filter(g.c, f.c, cname)
+	if c == nil {
+		return nil, errors.New("astiav: allocating filter context failed")
 	}
+	fc := newFilterContext(c)
+	g.fcs = append(g.fcs, fc)
 	return newBuffersrcFilterContext(fc), nil
 }
 

filter_graph_test.go

@@ -5,7 +5,6 @@ package astiav
 
 import (
 	"fmt"
-	"strconv"
 	"testing"
 
 	"github.com/stretchr/testify/require"
@@ -49,13 +48,24 @@ func TestFilterGraph(t *testing.T) {
 	type buffersrc struct {
 		name string
 	}
+	type buffersrcParameters struct {
+		channelLayout     ChannelLayout
+		height            int
+		mediaType         MediaType
+		pixelFormat       PixelFormat
+		sampleAspectRatio Rational
+		sampleFormat      SampleFormat
+		sampleRate        int
+		timeBase          Rational
+		width             int
+	}
 	type graph struct {
 		buffersink buffersink
 		buffersrc  buffersrc
 		commands   []command
 		content    string
 		s          string
-		sources    []FilterArgs
+		sources    []buffersrcParameters
 	}
 	for _, v := range []graph{
 		{
@@ -89,13 +99,14 @@ func TestFilterGraph(t *testing.T) {
 			},
 			content: "[input_1]scale=4x8,settb=1/4,fps=fps=4/1,format=pix_fmts=yuv420p,setsar=2/1",
 			s:       "                                                   +--------------+\nParsed_setsar_4:default--[4x8 2:1 yuv420p]--default|  filter_out  |\n                                                   | (buffersink) |\n                                                   +--------------+\n\n+-------------+\n| filter_in_1 |default--[2x4 1:2 rgba]--Parsed_scale_0:default\n|  (buffer)   |\n+-------------+\n\n                                            +----------------+\nfilter_in_1:default--[2x4 1:2 rgba]--default| Parsed_scale_0 |default--[4x8 1:2 yuv420p]--Parsed_settb_1:default\n                                            |    (scale)     |\n                                            +----------------+\n\n                                                  +----------------+\nParsed_scale_0:default--[4x8 1:2 yuv420p]--default| Parsed_settb_1 |default--[4x8 1:2 yuv420p]--Parsed_fps_2:default\n                                                  |    (settb)     |\n                                                  +----------------+\n\n                                                  +--------------+\nParsed_settb_1:default--[4x8 1:2 yuv420p]--default| Parsed_fps_2 |default--[4x8 1:2 yuv420p]--Parsed_format_3:default\n                                                  |    (fps)     |\n                                                  +--------------+\n\n                                                +-----------------+\nParsed_fps_2:default--[4x8 1:2 yuv420p]--default| Parsed_format_3 |default--[4x8 1:2 yuv420p]--Parsed_setsar_4:default\n                                                |    (format)     |\n                                                +-----------------+\n\n                                                   +-----------------+\nParsed_format_3:default--[4x8 1:2 yuv420p]--default| Parsed_setsar_4 |default--[4x8 2:1 yuv420p]--filter_out:default\n                                                   |    (setsar)     |\n                                                   +-----------------+\n\n",
-			sources: []FilterArgs{
+			sources: []buffersrcParameters{
 				{
-					"height":    "4",
-					"pix_fmt":   strconv.Itoa(int(PixelFormatRgba)),
-					"sar":       "1/2",
-					"time_base": "1/2",
-					"width":     "2",
+					height:            4,
+					mediaType:         MediaTypeVideo,
+					pixelFormat:       PixelFormatRgba,
+					sampleAspectRatio: NewRational(1, 2),
+					timeBase:          NewRational(1, 2),
+					width:             2,
 				},
 			},
 		},
@@ -111,12 +122,13 @@ func TestFilterGraph(t *testing.T) {
 			buffersrc: buffersrc{name: "abuffer"},
 			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{
+			sources: []buffersrcParameters{
 				{
-					"channel_layout": ChannelLayoutMono.String(),
-					"sample_fmt":     strconv.Itoa(int(SampleFormatFltp)),
-					"sample_rate":    "2",
-					"time_base":      "1/2",
+					channelLayout: ChannelLayoutMono,
+					mediaType:     MediaTypeAudio,
+					sampleFormat:  SampleFormatFltp,
+					sampleRate:    2,
+					timeBase:      NewRational(1, 2),
 				},
 			},
 		},
@@ -130,7 +142,7 @@ func TestFilterGraph(t *testing.T) {
 		buffersink := FindFilterByName(v.buffersink.name)
 		require.NotNil(t, buffersink)
 
-		buffersinkContext, err := fg.NewBuffersinkFilterContext(buffersink, "filter_out", nil)
+		buffersinkContext, err := fg.NewBuffersinkFilterContext(buffersink, "filter_out")
 		require.NoError(t, err)
 		cl = buffersinkContext.FilterContext().Class()
 		require.NotNil(t, cl)
@@ -152,8 +164,25 @@ func TestFilterGraph(t *testing.T) {
 
 		var buffersrcContexts []*BuffersrcFilterContext
 		for idx, src := range v.sources {
-			buffersrcContext, err := fg.NewBuffersrcFilterContext(buffersrc, fmt.Sprintf("filter_in_%d", idx+1), src)
+			buffersrcContext, err := fg.NewBuffersrcFilterContext(buffersrc, fmt.Sprintf("filter_in_%d", idx+1))
 			require.NoError(t, err)
+			buffersrcContextParameters := AllocBuffersrcFilterContextParameters()
+			defer buffersrcContextParameters.Free()
+			switch src.mediaType {
+			case MediaTypeAudio:
+				buffersrcContextParameters.SetChannelLayout(src.channelLayout)
+				buffersrcContextParameters.SetSampleFormat(src.sampleFormat)
+				buffersrcContextParameters.SetSampleRate(src.sampleRate)
+				buffersrcContextParameters.SetTimeBase(src.timeBase)
+			default:
+				buffersrcContextParameters.SetHeight(src.height)
+				buffersrcContextParameters.SetPixelFormat(src.pixelFormat)
+				buffersrcContextParameters.SetSampleAspectRatio(src.sampleAspectRatio)
+				buffersrcContextParameters.SetTimeBase(src.timeBase)
+				buffersrcContextParameters.SetWidth(src.width)
+			}
+			buffersrcContext.SetParameters(buffersrcContextParameters)
+			require.NoError(t, buffersrcContext.Initialize())
 			buffersrcContexts = append(buffersrcContexts, buffersrcContext)
 
 			o := AllocFilterInOut()