[feature] support processing of (many) more media types (#3090)

* initial work replacing our media decoding / encoding pipeline with ffprobe + ffmpeg

* specify the video codec to use when generating static image from emoji

* update go-storage library (fixes incompatibility after updating go-iotools)

* maintain image aspect ratio when generating a thumbnail for it

* update readme to show go-ffmpreg

* fix a bunch of media tests, move filesize checking to callers of media manager for more flexibility

* remove extra debug from error message

* fix up incorrect function signatures

* update PutFile to just use regular file copy, as changes are file is on separate partition

* fix remaining tests, remove some unneeded tests now we're working with ffmpeg/ffprobe

* update more tests, add more code comments

* add utilities to generate processed emoji / media outputs

* fix remaining tests

* add test for opus media file, add license header to utility cmds

* limit the number of concurrently available ffmpeg / ffprobe instances

* reduce number of instances

* further reduce number of instances

* fix envparsing test with configuration variables

* update docs and configuration with new media-{local,remote}-max-size variables

1 files changed, 0 insertions, 61 deletions

diff --git a/vendor/github.com/abema/go-mp4/internal/bitio/write.go b/vendor/github.com/abema/go-mp4/internal/bitio/write.go
deleted file mode 100644
index 5f63dd2d2..000000000
--- a/vendor/github.com/abema/go-mp4/internal/bitio/write.go
+++ /dev/null
@@ -1,61 +0,0 @@
-package bitio
-
-import (
-	"io"
-)
-
-type Writer interface {
-	io.Writer
-
-	// alignment:
-	//  |-1-byte-block-|--------------|--------------|--------------|
-	//  |<-offset->|<-------------------width---------------------->|
-	WriteBits(data []byte, width uint) error
-
-	WriteBit(bit bool) error
-}
-
-type writer struct {
-	writer io.Writer
-	octet  byte
-	width  uint
-}
-
-func NewWriter(w io.Writer) Writer {
-	return &writer{writer: w}
-}
-
-func (w *writer) Write(p []byte) (n int, err error) {
-	if w.width != 0 {
-		return 0, ErrInvalidAlignment
-	}
-	return w.writer.Write(p)
-}
-
-func (w *writer) WriteBits(data []byte, width uint) error {
-	length := uint(len(data)) * 8
-	offset := length - width
-	for i := offset; i < length; i++ {
-		oi := i / 8
-		if err := w.WriteBit((data[oi]>>(7-i%8))&0x01 != 0); err != nil {
-			return err
-		}
-	}
-	return nil
-}
-
-func (w *writer) WriteBit(bit bool) error {
-	if bit {
-		w.octet |= 0x1 << (7 - w.width)
-	}
-	w.width++
-
-	if w.width == 8 {
-		if _, err := w.writer.Write([]byte{w.octet}); err != nil {
-			return err
-		}
-		w.octet = 0x00
-		w.width = 0
-	}
-	return nil
-}