CEF/imagorvideoextended
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refactor(ffmpeg): refactor process frames

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* refactor best frame process

* refactor best frame process, remove alpha

* move thumb context to export

* process_frames() filter

* test: update golden files

* process_frames() filter

* test: update golden files

* tweak fps

* test: update golden files

* cleanup
This commit is contained in:
Adrian Shum 2022-10-13 15:23:23 +08:00 • committed by GitHub
parent c86b39430d
commit 4d71837fb8
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GPG key ID: 4AEE18F83AFDEB23
17 changed files with 127 additions and 122 deletions
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144
ffmpeg/ffmpeg.go
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@ -9,6 +9,7 @@ import (
"context"
"github.com/cshum/imagor/vips/pointer"
"io"
"math"
"time"
"unsafe"
)
@ -31,39 +32,37 @@ type Metadata struct {
FPS int `json:"fps,omitempty"`
HasVideo bool `json:"has_video"`
HasAudio bool `json:"has_audio"`
HasAlpha bool `json:"has_alpha"`
}
type AVContext struct {
context context.Context
opaque unsafe.Pointer
reader io.Reader
seeker io.Seeker
formatContext *C.AVFormatContext
stream *C.AVStream
codecContext *C.AVCodecContext
thumbContext *C.ThumbContext
selectedFrame *C.AVFrame
outputFrame *C.AVFrame
durationInFormat bool
context context.Context
opaque unsafe.Pointer
reader io.Reader
seeker io.Seeker
formatContext *C.AVFormatContext
stream *C.AVStream
codecContext *C.AVCodecContext
thumbContext *C.ThumbContext
selectedIndex C.int
frame *C.AVFrame
durationInFormat bool
orientation int
size int64
duration time.Duration
frameAt int
indexAt C.int
durationAt time.Duration
width, height int
title, artist string
hasVideo, hasAudio bool
hasAlpha bool
closed bool
}
func LoadAVContext(ctx context.Context, reader io.Reader, size int64) (*AVContext, error) {
av := &AVContext{
context: ctx,
reader: reader,
size: size,
context: ctx,
reader: reader,
size: size,
selectedIndex: -1,
}
if seeker, ok := reader.(io.Seeker); ok {
av.seeker = seeker
@ -81,36 +80,30 @@ func LoadAVContext(ctx context.Context, reader io.Reader, size int64) (*AVContex
if err := createDecoder(av); err != nil {
return av, err
}
if err := createThumbContext(av); err != nil {
return av, err
}
if err := convertFrameToRGB(av); err != nil {
return av, err
}
return av, nil
}
func closeAVContext(av *AVContext) {
if !av.closed {
if av.outputFrame != nil {
C.av_frame_free(&av.outputFrame)
}
if av.thumbContext != nil {
C.free_thumb_context(av.thumbContext)
av.selectedFrame = nil
}
if av.codecContext != nil {
C.avcodec_free_context(&av.codecContext)
}
if av.formatContext != nil {
C.free_format_context(av.formatContext)
}
pointer.Unref(av.opaque)
func (av *AVContext) ProcessFrames() (err error) {
if av.thumbContext == nil {
return createThumbContext(av)
}
return
}
func (av *AVContext) Export() (buf []byte, err error) {
return exportBuffer(av)
func (av *AVContext) Export(bands int) (buf []byte, err error) {
if err = av.ProcessFrames(); err != nil {
return
}
if av.selectedIndex < 0 {
findBestFrameIndex(av)
}
if bands < 3 || bands > 4 {
bands = 3
}
if err = convertFrameToRGB(av, bands); err != nil {
return
}
return exportBuffer(av, bands)
}
func (av *AVContext) Close() {
@ -120,7 +113,7 @@ func (av *AVContext) Close() {
func (av *AVContext) Metadata() *Metadata {
var fps float64
if av.durationAt > 0 {
fps = float64(av.frameAt) * float64(time.Second) / float64(av.durationAt)
fps = float64(av.indexAt) * float64(time.Second) / float64(av.durationAt)
}
return &Metadata{
Orientation: av.orientation,
@ -129,10 +122,28 @@ func (av *AVContext) Metadata() *Metadata {
Height: av.height,
Title: av.title,
Artist: av.artist,
FPS: int(fps),
FPS: int(math.Round(fps)),
HasVideo: av.hasVideo,
HasAudio: av.hasAudio,
HasAlpha: av.hasAlpha,
}
}
func closeAVContext(av *AVContext) {
if !av.closed {
if av.frame != nil {
C.av_frame_free(&av.frame)
}
if av.thumbContext != nil {
C.free_thumb_context(av.thumbContext)
}
if av.codecContext != nil {
C.avcodec_free_context(&av.codecContext)
}
if av.formatContext != nil {
C.free_format_context(av.formatContext)
}
pointer.Unref(av.opaque)
av.closed = true
}
}
@ -147,7 +158,7 @@ func createFormatContext(av *AVContext, callbackFlags C.int) error {
pointer.Unref(av.opaque)
return avError(intErr)
}
metaData(av)
metadata(av)
duration(av)
err := findStreams(av)
if err != nil {
@ -157,7 +168,7 @@ func createFormatContext(av *AVContext, callbackFlags C.int) error {
return err
}
func metaData(av *AVContext) {
func metadata(av *AVContext) {
var artist, title *C.char
C.get_metadata(av.formatContext, &artist, &title)
av.artist = C.GoString(artist)
@ -195,8 +206,8 @@ func createDecoder(av *AVContext) error {
return nil
}
func incrementDuration(av *AVContext, frame *C.AVFrame, i int) {
av.frameAt = i
func incrementDuration(av *AVContext, frame *C.AVFrame, i C.int) {
av.indexAt = i
if frame.pts != C.AV_NOPTS_VALUE {
ptsToNano := C.int64_t(1000000000 * av.stream.time_base.num / av.stream.time_base.den)
newDuration := time.Duration(frame.pts * ptsToNano)
@ -260,7 +271,7 @@ func populateThumbContext(av *AVContext, frames chan *C.AVFrame, done <-chan str
if err < 0 {
break
}
incrementDuration(av, frame, int(i))
incrementDuration(av, frame, i)
frames <- frame
frame = nil
}
@ -275,32 +286,31 @@ func populateThumbContext(av *AVContext, frames chan *C.AVFrame, done <-chan str
if err != 0 && err != C.int(ErrEOF) {
return avError(err)
}
av.selectedFrame = C.process_frames(av.thumbContext)
if av.selectedFrame == nil {
return ErrNoMem
}
av.hasAlpha = av.thumbContext.alpha != 0
return nil
}
func convertFrameToRGB(av *AVContext) error {
av.outputFrame = C.convert_frame_to_rgb(av.selectedFrame, av.thumbContext.alpha)
if av.outputFrame == nil {
func findBestFrameIndex(av *AVContext) {
av.selectedIndex = C.find_best_frame_index(av.thumbContext)
}
func convertFrameToRGB(av *AVContext, bands int) error {
var alpha int
if bands == 4 {
alpha = 1
}
av.frame = C.convert_frame_to_rgb(
C.select_frame(av.thumbContext, av.selectedIndex), C.int(alpha))
if av.frame == nil {
return ErrNoMem
}
return nil
}
func exportBuffer(av *AVContext) ([]byte, error) {
if av.outputFrame == nil {
func exportBuffer(av *AVContext, bands int) ([]byte, error) {
if av.frame == nil {
return nil, ErrInvalidData
}
size := av.height * av.width
if av.hasAlpha {
size *= 4
} else {
size *= 3
}
buf := C.GoBytes(unsafe.Pointer(av.outputFrame.data[0]), C.int(size))
size := av.height * av.width * bands
buf := C.GoBytes(unsafe.Pointer(av.frame.data[0]), C.int(size))
return buf, nil
}