import (
"context"
"fmt"
"io"
"os"
video "cloud.google.com/go/videointelligence/apiv1"
videopb "cloud.google.com/go/videointelligence/apiv1/videointelligencepb"
"github.com/golang/protobuf/ptypes"
)
// textDetection analyzes a video and extracts the text from the video's audio.
func textDetection(w io.Writer, filename string) error {
// filename := "../testdata/googlework_short.mp4"
ctx := context.Background()
// Creates a client.
client, err := video.NewClient(ctx)
if err != nil {
return fmt.Errorf("video.NewClient: %w", err)
}
defer client.Close()
fileBytes, err := os.ReadFile(filename)
if err != nil {
return fmt.Errorf("os.ReadFile: %w", err)
}
op, err := client.AnnotateVideo(ctx, &videopb.AnnotateVideoRequest{
InputContent: fileBytes,
Features: []videopb.Feature{
videopb.Feature_TEXT_DETECTION,
},
})
if err != nil {
return fmt.Errorf("AnnotateVideo: %w", err)
}
resp, err := op.Wait(ctx)
if err != nil {
return fmt.Errorf("Wait: %w", err)
}
// Only one video was processed, so get the first result.
result := resp.GetAnnotationResults()[0]
for _, annotation := range result.TextAnnotations {
fmt.Fprintf(w, "Text: %q\n", annotation.GetText())
// Get the first text segment.
segment := annotation.GetSegments()[0]
start, _ := ptypes.Duration(segment.GetSegment().GetStartTimeOffset())
end, _ := ptypes.Duration(segment.GetSegment().GetEndTimeOffset())
fmt.Fprintf(w, "\tSegment: %v to %v\n", start, end)
fmt.Fprintf(w, "\tConfidence: %f\n", segment.GetConfidence())
// Show the result for the first frame in this segment.
frame := segment.GetFrames()[0]
seconds := float32(frame.GetTimeOffset().GetSeconds())
nanos := float32(frame.GetTimeOffset().GetNanos())
fmt.Fprintf(w, "\tTime offset of the first frame: %fs\n", seconds+nanos/1e9)
fmt.Fprintf(w, "\tRotated bounding box vertices:\n")
for _, vertex := range frame.GetRotatedBoundingBox().GetVertices() {
fmt.Fprintf(w, "\t\tVertex x=%f, y=%f\n", vertex.GetX(), vertex.GetY())
}
}
return nil
}
