files: Ham Share's player — Auto quality, any by hand, or the file; 360 view; Transcode device setting
Every video plays YouTube's way: hls.js reads the connection and picks the quality, or one is picked by hand, or Original plays the file as it is. The qualities (a ladder by size, H.264) are made on the fly in 3 s pieces from wherever the viewer seeks, one ffmpeg per play, paused when far enough ahead. 360 videos open in a look-around view (drag, pinch or scroll to zoom from 8 to 300 degrees, phone motion). Settings -> Transcode device picks the machine and device that makes them, for every machine's files: a machine transcoding another's file reads it through the hub by a token for that one file. Replaces the codec/size picker and the single-quality re-encoder. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
This commit is contained in:
Mitchell-Johnson
co-authored by
Claude Opus 5.5
Claude Opus 5.5
parent
f5f1cd79ba
commit
fc4126a0ed
+244
-219
@@ -1,280 +1,305 @@
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package media
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// What to run when a file is to be re-encoded for a browser that cannot play it as it is:
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// the codecs and sizes on offer, the output size and bit rate a choice comes to for a
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// given source, the ways this machine could do it in the order worth trying, and the
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// ffmpeg argument list for one of them. All decisions, no processes, so it can be tested.
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// What to run when a video is played in the browser: the qualities it is offered in (the
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// ladder), the ways a machine could make one of them on the device asked for, in the order
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// worth trying, and the ffmpeg argument list for one piece-making run. All decisions, no
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// processes, so it can be tested. Everything is H.264 High and AAC: what every browser plays.
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import (
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"fmt"
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"math"
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"sort"
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"strconv"
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"strings"
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)
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// Codec is one target a stream may be re-encoded to. "copy" keeps the codec and only
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// repackages: for a browser that lacks the container, not the decoder.
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type Codec struct {
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ID string `json:"id"`
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Label string `json:"label"`
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// Rung is one quality the player can pick: a size, a frame rate and a bit rate.
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type Rung struct {
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Name string `json:"name"` // in URLs: the width, "1920"
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Label string `json:"label"` // what the menu says: "1080s", "720p"
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Width int `json:"width"`
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Height int `json:"height"`
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FPS float64 `json:"fps"`
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Bitrate int `json:"bitrate"` // video, bits a second, on average
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Peak int `json:"peak"` // what the playlist promises, sound included
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level string // H.264 level, "5.2"
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codecs string // for the master playlist
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}
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var Codecs = []Codec{{"h264", "H.264"}, {"hevc", "HEVC"}, {"av1", "AV1"}, {"copy", "Original codec, repackaged"}}
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// Quality is a picture height; the bit rate follows from the size the output ends up at.
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type Quality struct {
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ID string `json:"id"`
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Label string `json:"label"`
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Height int `json:"height"` // 0: the source's own
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// One step of the ladder: the long side for a 360 video (its width), the short side for a flat
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// one, and the bit rate (Mb/s ×10) at more than 30 frames a second and at 30 or fewer.
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type step struct {
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size int
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label string
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hi, lo int
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cap30 bool
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}
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var Qualities = []Quality{{"original", "Original size", 0}, {"1080p", "1080p", 1080}, {"720p", "720p", 720}, {"480p", "480p", 480}}
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// A 360 picture is seen a quarter of its width at a time, so it needs more pixels than a flat
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// one for the same sharpness; YouTube names its sizes by the flat picture they look like
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// ("1080s"), and so does this.
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var vrSteps = []step{
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{3840, "2160s", 220, 160, false},
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{2880, "1440s", 120, 90, false},
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{1920, "1080s", 60, 45, false},
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{1280, "720s", 25, 25, true},
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}
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func qualityByID(id string) (Quality, bool) {
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for _, q := range Qualities {
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if q.ID == id {
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return q, true
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var flatSteps = []step{
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{2160, "2160p", 160, 120, false},
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{1440, "1440p", 90, 65, false},
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{1080, "1080p", 50, 35, false},
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{720, "720p", 25, 25, true},
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{480, "480p", 12, 12, true},
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}
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const audioRate = 160_000
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func even(x float64) int { return int(math.Round(x/2)) * 2 }
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// Ladder is the qualities a video is offered in, best first: every step no bigger than the
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// picture itself, or the picture's own size if it is smaller than all of them.
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func Ladder(i Info) []Rung {
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v := i.Video
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if v == nil || v.Width <= 0 || v.Height <= 0 {
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return nil
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}
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vr := v.Spherical
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steps := flatSteps
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src := min(v.Width, v.Height) // a flat picture is named by its short side
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if vr {
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steps, src = vrSteps, v.Width
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}
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// A picture between two steps (a 2292×960 capture) gets its own size on top, at the bit
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// rate of the step above, so the best on offer is never less than the file.
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var out []Rung
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for k, s := range steps {
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if s.size > src {
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continue
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}
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}
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return Quality{}, false
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}
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// ValidChoice says whether a codec and quality are ones on offer — checked before any work.
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func ValidChoice(codec, quality string) error {
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if !codecKnown(codec) {
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return fmt.Errorf("unknown codec %q", codec)
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}
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if _, ok := qualityByID(quality); !ok {
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return fmt.Errorf("unknown quality %q", quality)
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}
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return nil
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}
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func codecKnown(id string) bool {
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for _, c := range Codecs {
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if c.ID == id {
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return true
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if len(out) == 0 && s.size < src && k > 0 { // never above the top step: H.264 stops there
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own := steps[k-1]
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own.size, own.label, own.cap30 = src, strconv.Itoa(src)+map[bool]string{true: "s", false: "p"}[vr], false
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out = append(out, rung(i, own))
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}
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out = append(out, rung(i, s))
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}
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return false
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if len(out) == 0 {
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last := steps[len(steps)-1]
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last.size, last.label = src, strconv.Itoa(src)+map[bool]string{true: "s", false: "p"}[vr]
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out = append(out, rung(i, last))
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}
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return out
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}
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// fit is the output: never larger than the source, even dimensions, and a bit rate by the
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// size it comes to — a quarter more at 50 fps and up, less for the codecs that need less.
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func fit(q Quality, src Info, codec string) (w, h, kbps int) {
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w, h = src.Video.Width, src.Video.Height
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if q.Height > 0 && h > q.Height {
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w = int(math.Round(float64(w) * float64(q.Height) / float64(h)))
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h = q.Height
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}
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w, h = w&^1, h&^1
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func rung(i Info, s step) Rung {
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v := i.Video
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var w, h int
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switch {
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case h >= 2160:
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kbps = 20000
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case h >= 1440:
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kbps = 12000
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case h >= 1080:
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kbps = 8000
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case h >= 720:
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kbps = 4000
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default:
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kbps = 2000
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case v.Spherical:
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w, h = s.size, even(float64(s.size)*float64(v.Height)/float64(v.Width))
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case v.Width >= v.Height:
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h, w = s.size, even(float64(s.size)*float64(v.Width)/float64(v.Height))
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default: // standing up
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w, h = s.size, even(float64(s.size)*float64(v.Height)/float64(v.Width))
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}
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if src.Video.FPS >= 50 {
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kbps = kbps * 5 / 4
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fps := v.FPS
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if fps <= 0 {
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fps = 30
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}
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if codec == "hevc" || codec == "av1" {
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kbps = kbps * 6 / 10
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for fps > 60.5 || (s.cap30 && fps > 30.5) {
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fps /= 2
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}
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return w, h, kbps
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fps = math.Round(fps*1000) / 1000
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br := s.lo
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if fps > 30.5 {
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br = s.hi
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}
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r := Rung{Name: strconv.Itoa(w), Label: s.label, Width: w, Height: h, FPS: fps, Bitrate: br * 100_000}
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r.Peak = r.Bitrate*3/2 + audioRate
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r.level = level(w, h, fps)
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lv, _ := strconv.ParseFloat(r.level, 64)
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r.codecs = fmt.Sprintf("avc1.6400%02x", int(math.Round(lv*10)))
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if i.Audio != nil {
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r.codecs += ",mp4a.40.2"
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}
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return r
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}
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// Recipe is one way to make the stream: the engine's name for the record, and the ffmpeg
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// arguments that go before the input, the video filter, and the video codec.
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// level is the lowest H.264 level that takes this many macroblocks a frame and a second.
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func level(w, h int, fps float64) string {
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mbs := ((w + 15) / 16) * ((h + 15) / 16)
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rate := float64(mbs) * fps
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for _, l := range []struct {
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name string
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mbps float64
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frame int
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}{
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{"3.1", 108000, 3600}, {"3.2", 216000, 5120}, {"4.0", 245760, 8192}, {"4.2", 522240, 8704},
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{"5.0", 589824, 22080}, {"5.1", 983040, 36864}, {"5.2", 2073600, 36864},
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} {
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if rate <= l.mbps && mbs <= l.frame {
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return l.name
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}
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}
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return "6.2"
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}
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// fpsArg is a frame rate as ffmpeg's fps filter takes it, exactly for the NTSC rates.
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func fpsArg(f float64) string {
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for _, n := range []float64{24, 30, 60, 120} {
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if math.Abs(f-n*1000/1001) < 0.01 {
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return fmt.Sprintf("%d/1001", int(n*1000))
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}
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}
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return strings.TrimRight(strings.TrimRight(strconv.FormatFloat(f, 'f', 3, 64), "0"), ".")
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}
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// Recipe is one way to make a quality: the engine's name for the record, the device it runs
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// on ("cpu" for the software encoder), and the ffmpeg arguments that go before the input, the
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// video filter, and the video codec.
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type Recipe struct {
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Engine string
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Device string
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Pre []string
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VF string
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Video []string
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}
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// recipes are the ways to try, best first: a card on the bus before the integrated GPU;
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// on a GPU, decoding on the same card (frames never leave it) before decoding in software
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// and uploading; the software encoders last. An empty list means nothing here can.
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func recipes(c Caps, codec string, src Info, w, h, kbps int) []Recipe {
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if codec == "copy" {
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v := []string{"-c:v", "copy"}
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if src.Video.Codec == "hevc" {
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v = append(v, "-tag:v", "hvc1") // Safari reads hvc1, not hev1
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}
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return []Recipe{{Engine: "Original codec", Video: v}}
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// CPU is the device name for software encoding.
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const CPU = "cpu"
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// Device is one thing a machine can make H.264 on, for the Transcode device setting.
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type Device struct {
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ID string `json:"id"` // a render node, or "cpu"
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Name string `json:"name"` // "Intel Arc A380", "CPU (libx264)"
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Integrated bool `json:"integrated,omitempty"`
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OK bool `json:"ok"`
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Reason string `json:"reason,omitempty"` // when not OK: why
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}
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// Devices lists what this machine could make the player's H.264 on: every GPU, usable or not
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// (and why not), then the CPU.
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func Devices(c Caps) []Device {
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var out []Device
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if c.Error != "" {
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return []Device{{ID: CPU, Name: "CPU", Reason: c.Error}}
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}
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var out []Recipe
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gpus := append([]GPU(nil), c.GPUs...)
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sort.SliceStable(gpus, func(i, j int) bool { return !gpus[i].Integrated && gpus[j].Integrated })
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rate := []string{"-b:v", strconv.Itoa(kbps) + "k", "-maxrate", strconv.Itoa(kbps*5/4) + "k", "-bufsize", strconv.Itoa(kbps*5/2) + "k"}
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for i := range gpus {
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g := &gpus[i]
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if g.API != "vaapi" || !has(g.Encodes, codec) {
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continue
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for _, g := range c.GPUs {
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d := Device{ID: g.Device, Name: g.Name, Integrated: g.Integrated}
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if d.Name == "" {
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d.Name = g.Device
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}
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video := append([]string{"-c:v", codec + "_vaapi"}, rate...)
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switch codec {
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case "h264":
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video = append(video, "-profile:v", "high")
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case "hevc":
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video = append(video, "-tag:v", "hvc1")
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switch {
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case g.API != "vaapi":
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d.Reason = "only VAAPI devices encode here"
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case !has(g.Encodes, "h264"):
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d.Reason = "doesn't encode H.264"
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default:
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d.OK = true
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}
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out = append(out, d)
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}
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for _, g := range c.Unusable {
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name := g.Name
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if name == "" {
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name = g.Device
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}
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scale := fmt.Sprintf("scale_vaapi=w=%d:h=%d:format=nv12", w, h)
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if has(g.Codecs, src.Video.Codec) {
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vf := scale
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if src.HDR() {
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vf = "tonemap_vaapi=format=nv12:t=bt709:p=bt709:m=bt709," + vf
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out = append(out, Device{ID: g.Device, Name: name, Integrated: g.Integrated, Reason: g.Reason})
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}
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d := Device{ID: CPU, Name: "CPU (libx264)", OK: has(c.Encoders, "libx264")}
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if !d.OK {
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d.Reason = "this ffmpeg has no libx264"
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}
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return append(out, d)
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}
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// recipes are the ways to make quality r of src on device, best first: on a GPU, decoding on
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// the same card (frames never leave it) before decoding in software and uploading; the CPU
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// last, as the fallback whatever was asked. device "" is any: a card on the bus before the
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// integrated GPU. An empty list means nothing here can.
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func recipes(c Caps, device string, src Info, r Rung) []Recipe {
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var out []Recipe
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gpus := append([]GPU(nil), c.GPUs...)
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sort.SliceStable(gpus, func(i, j int) bool { return !gpus[i].Integrated && gpus[j].Integrated })
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kbps := r.Bitrate / 1000
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rate := []string{"-b:v", strconv.Itoa(kbps) + "k", "-maxrate", strconv.Itoa(kbps*3/2) + "k", "-bufsize", strconv.Itoa(kbps*2) + "k",
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"-profile:v", "high", "-level", r.level}
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fps := ""
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if src.Video == nil || src.Video.FPS <= 0 || math.Abs(src.Video.FPS-r.FPS) > 0.01 {
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fps = "fps=" + fpsArg(r.FPS) + ","
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}
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if device != CPU {
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for i := range gpus {
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g := &gpus[i]
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if g.API != "vaapi" || !has(g.Encodes, "h264") || (device != "" && g.Device != device) {
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continue
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}
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out = append(out, Recipe{Engine: name + " (vaapi)", Pre: []string{"-hwaccel", "vaapi", "-hwaccel_device", g.Device, "-hwaccel_output_format", "vaapi"}, VF: vf, Video: video})
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video := append(append([]string{"-c:v", "h264_vaapi"}, rate...), "-bf", "0")
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name := g.Name
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if name == "" {
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name = g.Device
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}
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scale := fmt.Sprintf("scale_vaapi=w=%d:h=%d:format=nv12", r.Width, r.Height)
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if src.Video != nil && has(g.Codecs, src.Video.Codec) {
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vf := fps + scale
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if src.HDR() {
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vf = fps + "tonemap_vaapi=format=nv12:t=bt709:p=bt709:m=bt709," + scale
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}
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out = append(out, Recipe{Engine: name, Device: g.Device, Pre: []string{"-hwaccel", "vaapi", "-hwaccel_device", g.Device, "-hwaccel_output_format", "vaapi"}, VF: vf, Video: video})
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}
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out = append(out, Recipe{Engine: name + ", decoded on the CPU", Device: g.Device, Pre: []string{"-init_hw_device", "vaapi=va:" + g.Device, "-filter_hw_device", "va"},
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VF: fmt.Sprintf("%sformat=nv12,scale=%d:%d,hwupload", fps, r.Width, r.Height), Video: video})
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}
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out = append(out, Recipe{Engine: name + " (vaapi, decoded on the CPU)", Pre: []string{"-init_hw_device", "vaapi=va:" + g.Device, "-filter_hw_device", "va"},
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VF: fmt.Sprintf("format=nv12,scale=%d:%d,hwupload", w, h), Video: video})
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}
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swVF := fmt.Sprintf("scale=%d:%d,format=yuv420p", w, h)
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if src.HDR() {
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swVF = fmt.Sprintf("zscale=t=linear:npl=100,format=gbrpf32le,zscale=p=bt709,tonemap=hable,zscale=t=bt709:m=bt709,scale=%d:%d,format=yuv420p", w, h)
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}
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cap := []string{"-maxrate", strconv.Itoa(kbps*5/4) + "k", "-bufsize", strconv.Itoa(kbps*5/2) + "k"}
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switch {
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case codec == "h264" && has(c.Encoders, "libx264"):
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out = append(out, Recipe{Engine: "CPU (libx264)", VF: swVF, Video: append([]string{"-c:v", "libx264", "-preset", "veryfast", "-crf", "23", "-profile:v", "high"}, cap...)})
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case codec == "hevc" && has(c.Encoders, "libx265"):
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out = append(out, Recipe{Engine: "CPU (libx265)", VF: swVF, Video: append([]string{"-c:v", "libx265", "-preset", "fast", "-crf", "26", "-tag:v", "hvc1"}, cap...)})
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case codec == "av1" && has(c.Encoders, "libsvtav1"):
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out = append(out, Recipe{Engine: "CPU (SVT-AV1)", VF: swVF, Video: append([]string{"-c:v", "libsvtav1", "-preset", "8", "-crf", "35"}, cap...)})
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if has(c.Encoders, "libx264") {
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vf := fmt.Sprintf("%sscale=%d:%d,format=yuv420p", fps, r.Width, r.Height)
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if src.HDR() {
|
||||
vf = fmt.Sprintf("%szscale=t=linear:npl=100,format=gbrpf32le,zscale=p=bt709,tonemap=hable,zscale=t=bt709:m=bt709,scale=%d:%d,format=yuv420p", fps, r.Width, r.Height)
|
||||
}
|
||||
out = append(out, Recipe{Engine: "CPU (libx264)", Device: CPU, VF: vf, Video: append([]string{"-c:v", "libx264", "-preset", "veryfast", "-sc_threshold", "0"}, rate...)})
|
||||
}
|
||||
return out
|
||||
}
|
||||
|
||||
// EngineFor is the engine the picker will say a codec runs on, "" when none can.
|
||||
func EngineFor(c Caps, codec string) string {
|
||||
if c.Error != "" {
|
||||
return ""
|
||||
}
|
||||
if codec == "copy" {
|
||||
return "Original codec"
|
||||
}
|
||||
r := recipes(c, codec, Info{Video: &Track{Codec: "h264", Width: 1920, Height: 1080}}, 1920, 1080, 8000)
|
||||
if len(r) == 0 {
|
||||
return ""
|
||||
}
|
||||
return r[0].Engine
|
||||
}
|
||||
// Seg is the length of a piece, in seconds.
|
||||
const Seg = 3.0
|
||||
|
||||
// hlsArgs is the whole ffmpeg argument list for one recipe: the input, the first video and
|
||||
// audio streams, the picture through the recipe, sound as AAC unless it already is, a
|
||||
// keyframe every segment, and an event playlist of fragmented-MP4 segments in dir.
|
||||
func hlsArgs(dir, in string, src Info, r Recipe, copyCodec bool) []string {
|
||||
a := []string{"-nostdin", "-hide_banner", "-loglevel", "error", "-y"}
|
||||
a = append(a, r.Pre...)
|
||||
a = append(a, "-i", in, "-map", "0:v:0", "-map", "0:a:0?", "-sn", "-dn")
|
||||
if r.VF != "" {
|
||||
a = append(a, "-vf", r.VF)
|
||||
}
|
||||
a = append(a, r.Video...)
|
||||
switch {
|
||||
case src.Audio == nil:
|
||||
a = append(a, "-an")
|
||||
case src.Audio.Codec == "aac":
|
||||
a = append(a, "-c:a", "copy")
|
||||
default:
|
||||
a = append(a, "-c:a", "aac", "-b:a", "160k", "-ac", "2")
|
||||
}
|
||||
if !copyCodec {
|
||||
fps := src.Video.FPS
|
||||
if fps <= 0 {
|
||||
fps = 30
|
||||
}
|
||||
gop := int(math.Round(fps * hlsSeconds))
|
||||
if gop < 24 {
|
||||
gop = 24
|
||||
}
|
||||
if gop > 300 {
|
||||
gop = 300
|
||||
}
|
||||
a = append(a, "-g", strconv.Itoa(gop), "-force_key_frames", fmt.Sprintf("expr:gte(t,n_forced*%d)", hlsSeconds))
|
||||
}
|
||||
a = append(a, "-f", "hls", "-hls_time", strconv.Itoa(hlsSeconds), "-hls_playlist_type", "event", "-hls_segment_type", "fmp4",
|
||||
"-hls_fmp4_init_filename", "init.mp4", "-hls_segment_filename", dir+"/seg%05d.m4s", "-hls_flags", "independent_segments+temp_file",
|
||||
"-progress", dir+"/progress", "-stats_period", "1", dir+"/index.m3u8")
|
||||
return a
|
||||
}
|
||||
|
||||
const hlsSeconds = 4
|
||||
|
||||
// tsBase is added to every run's timestamps. A run from the top would otherwise start just
|
||||
// below zero (the B-frame delay) and the muxer would shift it to make room, while a run from a
|
||||
// seek point would not: with the base, no run is ever shifted, and a segment means the same
|
||||
// stretch of the film whichever run made it.
|
||||
// tsBase is added to every run's times, so pieces from different runs follow on: without it
|
||||
// a run from the top would start just below zero (the B-frame and AAC delay) and the muxer
|
||||
// would shift that run alone.
|
||||
const tsBase = 10
|
||||
|
||||
// segArgs is one run of a seekable re-encode: segments from..to-1 of the fixed 4 s grid.
|
||||
// Every run is made the same way, the first included, so their segments are interchangeable:
|
||||
// an accurate seek to from×4 s, timestamps put back where that is in the film (+ tsBase),
|
||||
// kept as they are in each fragment (frag_discont), numbered from `from`, and an end just
|
||||
// short of segment `to`, which is already on disk, so the run never writes over it. Segments
|
||||
// land in dir as seg%05d.m4s; init is the init segment's name (only the first run's is used).
|
||||
func segArgs(dir, in string, src Info, r Recipe, from, to, n int, init string) []string {
|
||||
fps := 30.0
|
||||
if src.Video != nil && src.Video.FPS > 0 {
|
||||
fps = src.Video.FPS
|
||||
}
|
||||
start := from * hlsSeconds
|
||||
// pieceArgs is one run making quality r from piece n on, into dir as <n>.ts: an accurate seek
|
||||
// to n×Seg, a keyframe on every Seg mark and nowhere else (so every piece starts on one, and
|
||||
// pieces from any run and quality line up), times put back where that is in the film. in is a
|
||||
// path or, for a file on another machine, an http URL.
|
||||
func pieceArgs(dir, in string, src Info, rc Recipe, r Rung, n int) []string {
|
||||
at := strconv.FormatFloat(float64(n)*Seg, 'f', 3, 64)
|
||||
a := []string{"-nostdin", "-hide_banner", "-loglevel", "error", "-y"}
|
||||
a = append(a, r.Pre...)
|
||||
a = append(a, "-ss", strconv.Itoa(start), "-i", in, "-map", "0:v:0", "-map", "0:a:0?", "-sn", "-dn")
|
||||
if r.VF != "" {
|
||||
a = append(a, "-vf", r.VF)
|
||||
a = append(a, rc.Pre...)
|
||||
if strings.HasPrefix(in, "http://") || strings.HasPrefix(in, "https://") {
|
||||
a = append(a, "-reconnect", "1", "-reconnect_on_network_error", "1", "-reconnect_delay_max", "4")
|
||||
}
|
||||
a = append(a, r.Video...)
|
||||
switch {
|
||||
case src.Audio == nil:
|
||||
a = append(a, "-ss", at, "-i", in, "-map", "0:v:0", "-map", "0:a:0?", "-sn", "-dn")
|
||||
if rc.VF != "" {
|
||||
a = append(a, "-vf", rc.VF)
|
||||
}
|
||||
a = append(a, rc.Video...)
|
||||
if src.Audio == nil {
|
||||
a = append(a, "-an")
|
||||
case src.Audio.Codec == "aac":
|
||||
a = append(a, "-c:a", "copy")
|
||||
default:
|
||||
} else {
|
||||
a = append(a, "-c:a", "aac", "-b:a", "160k", "-ac", "2")
|
||||
}
|
||||
gop := int(math.Round(fps * hlsSeconds))
|
||||
if gop < 24 {
|
||||
gop = 24
|
||||
}
|
||||
if gop > 300 {
|
||||
gop = 300
|
||||
}
|
||||
a = append(a, "-g", strconv.Itoa(gop), "-force_key_frames", fmt.Sprintf("expr:gte(t,n_forced*%d)", hlsSeconds))
|
||||
if to < n {
|
||||
a = append(a, "-t", strconv.FormatFloat(float64((to-from)*hlsSeconds)-0.5/fps, 'f', 3, 64))
|
||||
}
|
||||
a = append(a, "-output_ts_offset", strconv.Itoa(start+tsBase),
|
||||
"-f", "hls", "-hls_time", strconv.Itoa(hlsSeconds), "-hls_playlist_type", "event", "-hls_segment_type", "fmp4",
|
||||
"-hls_segment_options", "movflags=+frag_discont", "-start_number", strconv.Itoa(from),
|
||||
"-hls_fmp4_init_filename", init, "-hls_segment_filename", dir+"/seg%05d.m4s", "-hls_flags", "independent_segments+temp_file",
|
||||
"-progress", dir+"/progress", "-stats_period", "1", dir+"/run.m3u8")
|
||||
gop := int(math.Ceil(r.FPS*Seg)) * 4
|
||||
a = append(a, "-g", strconv.Itoa(gop), "-force_key_frames", fmt.Sprintf("expr:gte(t,n_forced*%g)", Seg),
|
||||
"-output_ts_offset", strconv.FormatFloat(float64(n)*Seg+tsBase, 'f', 3, 64),
|
||||
"-f", "hls", "-hls_time", strconv.FormatFloat(Seg-0.5, 'f', 2, 64), "-hls_list_size", "0",
|
||||
"-hls_flags", "temp_file", "-hls_segment_type", "mpegts", "-start_number", strconv.Itoa(n),
|
||||
"-hls_segment_filename", dir+"/%d.ts", dir+"/ffmpeg.m3u8")
|
||||
return a
|
||||
}
|
||||
|
||||
// segCount is how many 4 s segments a seekable re-encode of a file this long lists. The last
|
||||
// 0.3 s are left out of the count, so a container whose sound runs on past the picture never
|
||||
// lists a segment no frame starts.
|
||||
func segCount(duration float64) int {
|
||||
d := duration - 0.3
|
||||
if d < 0 {
|
||||
d = 0
|
||||
}
|
||||
return int(d/hlsSeconds) + 1
|
||||
}
|
||||
|
||||
func has(list []string, x string) bool {
|
||||
for _, v := range list {
|
||||
if v == x {
|
||||
|
||||
Reference in New Issue
Block a user