$ get_iplayer --raw --modes=flashhd --rtmpdump=./rtmpdump http://www.bbc.co.uk/iplayer/episode/b03tvhy0/hd/Winter_Olympics_Sochi_2014_Opening_Ceremony/
get_iplayer 2.85.0.0, Copyright (C) 2008-2010 Phil Lewis
  This program comes with ABSOLUTELY NO WARRANTY; for details use --warranty.
  This is free software, and you are welcome to redistribute it under certain
  conditions; use --conditions for details.

INFO: Episode-only pid detected
INFO: Trying pid: b03tvhy0 using type: tv
INFO Trying to stream pid using type tv
INFO: pid found in cache
Matches:
1232:	Winter Olympics - Sochi 2014: Opening Ceremony, BBC Sport, Guidance,Sport,TV,Winter Olympics,Winter Sports, default

INFO: 1 Matching Programmes
INFO: Checking existence of default version
INFO: flashhd1,flashhd2 modes will be tried for version default
INFO: Trying flashhd1 mode to record tv: Winter Olympics - Sochi 2014: Opening Ceremony
INFO: File name prefix = Winter_Olympics_-_Sochi_2014_Opening_Ceremony_b03tvhy0_default                 
RTMPDump v2.4
(c) 2010 Andrej Stepanchuk, Howard Chu, The Flvstreamer Team; license: GPL
Connecting ...
INFO: Connected...
Starting download at: 0.000 kB
INFO: Metadata:
INFO:   duration              14349.68
INFO:   moovPosition          36.00
INFO:   width                 1280.00
INFO:   height                720.00
INFO:   videocodecid          avc1
INFO:   audiocodecid          mp4a
INFO:   avcprofile            100.00
INFO:   avclevel              41.00
INFO:   aacaot                2.00
INFO:   videoframerate        25.00
INFO:   audiosamplerate       48000.00
INFO:   audiochannels         2.00
INFO: trackinfo:
INFO:   length                358742000.00
INFO:   timescale             25000.00
INFO:   language              und
INFO: sampledescription:
INFO:   sampletype            avc1
INFO:   length                688783360.00
INFO:   timescale             48000.00
INFO:   language              und
INFO: sampledescription:
INFO:   sampletype            mp4a
4216295.098 kB / 14349.64 sec (99.9%)
Download complete

$ mediainfo Winter_Olympics_-_Sochi_2014_Opening_Ceremony_b03tvhy0_default.flv
General
Complete name                            : Winter_Olympics_-_Sochi_2014_Opening_Ceremony_b03tvhy0_default.flv
Format                                   : Flash Video
File size                                : 4.02 GiB
Duration                                 : 3h 59mn
Overall bit rate mode                    : Variable
Overall bit rate                         : 2 407 Kbps

Video
Format                                   : AVC
Format/Info                              : Advanced Video Codec
Format profile                           : High@L4.1
Format settings, CABAC                   : Yes
Format settings, ReFrames                : 2 frames
Codec ID                                 : 7
Duration                                 : 3h 59mn
Bit rate mode                            : Variable
Maximum bit rate                         : 3 500 Kbps
Width                                    : 1 280 pixels
Height                                   : 720 pixels
Display aspect ratio                     : 16:9
Frame rate mode                          : Constant
Frame rate                               : 25.000 fps
Color space                              : YUV
Chroma subsampling                       : 4:2:0
Bit depth                                : 8 bits
Scan type                                : Progressive

Audio
Format                                   : AAC
Format/Info                              : Advanced Audio Codec
Format profile                           : LC
Codec ID                                 : 10
Duration                                 : 3h 59mn
Channel count                            : 2 channels
Channel positions                        : Front: L R
Sampling rate                            : 48.0 KHz
Compression mode                         : Lossy