Add lab restream pipeline with pirate_drift logo and lib/env.sh.

Encode-once/fanout scripts, HLS output, and single overloadable env source.
Commits assets/pirate_drift.png as default watermark for cluster runs.

Co-authored-by: Cursor <cursoragent@cursor.com>

lib/source.sh

@@ -0,0 +1,118 @@
+#!/usr/bin/env bash
+# Resolve pipeline input from CLI arg, sources.list index, or env SOURCE_URL.
+set -euo pipefail
+
+# shellcheck disable=SC1091
+source "$(dirname "${BASH_SOURCE[0]}")/common.sh"
+
+SOURCE_URL=""
+SOURCE_FMT=""
+SOURCE_VIDEO_STREAM="v:0"
+SOURCE_AUDIO_STREAM="a:0"
+AUDIO_INPUT_ARGS=()
+USE_YTDLP=0
+
+is_page_url() {
+  local url="$1"
+  [[ "$url" =~ ^https?:// ]] || return 1
+  [[ "$url" =~ \.(m3u8|mpd|mp4|mkv|mov|ts|flv)(\?|$) ]] && return 1
+  [[ -f "$url" ]] && return 1
+  return 0
+}
+
+resolve_source() {
+  local arg="${1:-}"
+  SOURCE_URL="${SOURCE_URL:-}"
+  SOURCE_FMT=""
+
+  if [[ -n "${SOURCE_URL}" ]]; then
+    :
+  elif [[ -n "${arg}" && -f "${arg}" && "${arg}" != *".list" ]]; then
+    SOURCE_URL="${arg}"
+  elif [[ -n "${arg}" && "${arg}" =~ ^https?:// ]]; then
+    SOURCE_URL="${arg}"
+  elif [[ -n "${arg}" && "${arg}" =~ ^[0-9]+$ ]]; then
+    if [[ ! -f "${SOURCES_LIST}" ]]; then
+      die "sources list missing: ${SOURCES_LIST} (copy sources.example.list)"
+    fi
+    local line
+    line="$(sed -n "${arg}p" "${SOURCES_LIST}" | sed 's/#.*//' | sed 's/^[[:space:]]*//;s/[[:space:]]*$//')"
+    [[ -n "${line}" ]] || die "no source on line ${arg} of ${SOURCES_LIST}"
+    SOURCE_URL="$(awk '{print $1}' <<<"${line}")"
+    SOURCE_FMT="$(awk '{print $2}' <<<"${line}")"
+  elif [[ -f "${SOURCES_LIST}" ]]; then
+    local line
+    line="$(grep -v '^[[:space:]]*#' "${SOURCES_LIST}" | grep -v '^[[:space:]]*$' | head -1)"
+    SOURCE_URL="$(awk '{print $1}' <<<"${line}")"
+    SOURCE_FMT="$(awk '{print $2}' <<<"${line}")"
+  else
+    die "usage: pass URL, file path, or 1-based index into ${SOURCES_LIST}"
+  fi
+
+  [[ -n "${SOURCE_URL}" ]] || die "empty source URL"
+
+  if [[ -n "${AUDIO_SOURCE:-}" ]]; then
+    read_rate_flag
+    AUDIO_INPUT_ARGS=("${RE_FLAG[@]}" -thread_queue_size "${THREAD_QUEUE_SIZE}" -i "${AUDIO_SOURCE}")
+    SOURCE_AUDIO_STREAM="a:0"
+  fi
+
+  if [[ "${YTDLP_ENABLED}" == "1" ]] && is_page_url "${SOURCE_URL}"; then
+    USE_YTDLP=1
+  fi
+
+  echo "${SOURCE_URL}" > "${ROOT}/.current_source"
+  log "source: ${SOURCE_URL} (ytdlp=${USE_YTDLP})"
+}
+
+ytdlp_auth_args() {
+  local auth="${ROOT}/config/yt-dlp.auth.env"
+  if [[ -f "${auth}" ]]; then
+    # shellcheck disable=SC1090
+    source "${auth}"
+  fi
+  local args=()
+  [[ -n "${YTDLP_USERNAME:-}" ]] && args+=(--username "${YTDLP_USERNAME}")
+  [[ -n "${YTDLP_PASSWORD:-}" ]] && args+=(--password "${YTDLP_PASSWORD}")
+  [[ -n "${YTDLP_NETRC:-}" ]] && args+=(--netrc)
+  [[ -n "${YTDLP_EXTRA_ARGS:-}" ]] && args+=(${YTDLP_EXTRA_ARGS})
+  printf '%s\n' "${args[@]}"
+}
+
+build_ytdlp_pipeline() {
+  local fmt_args=()
+  [[ -n "${SOURCE_FMT}" ]] && fmt_args=(-f "${SOURCE_FMT}")
+  mapfile -t auth < <(ytdlp_auth_args)
+
+  printf '%s\0' "${YTDLP_BIN}" \
+    -o - --no-part --no-live-from-start --no-write-subs --no-embed-subs \
+    --remux-video mkv --merge-output-format mkv --no-audio-multistreams \
+    --geo-bypass --ignore-errors --hls-use-mpegts \
+    "${auth[@]}" \
+    "${fmt_args[@]}" \
+    "${SOURCE_URL}"
+}
+
+# Returns ffmpeg input argv: either direct -i URL or pipe from yt-dlp.
+build_primary_input() {
+  read_rate_flag
+  if [[ "${USE_YTDLP}" == "1" ]]; then
+    require_cmd "${YTDLP_BIN}"
+    printf '%s\0' pipe
+    printf '%s\0' -thread_queue_size "${THREAD_QUEUE_SIZE}" -i pipe:0
+    return
+  fi
+
+  local url="${SOURCE_URL}"
+  if [[ "${url}" == *.jpg || "${url}" == *.jpeg || "${url}" == *.png ]]; then
+    printf '%s\0' direct
+    printf '%s\0' "${RE_FLAG[@]}" -thread_queue_size "${THREAD_QUEUE_SIZE}" \
+      -loop 1 -i "${url}" -f lavfi -i anullsrc=channel_layout=stereo:sample_rate=48000
+    return
+  fi
+
+  printf '%s\0' direct
+  printf '%s\0' "${RE_FLAG[@]}" -thread_queue_size "${THREAD_QUEUE_SIZE}" \
+    -reconnect_on_network_error 1 -reconnect_streamed 1 -reconnect_delay_max 5 \
+    -i "${url}"
+}