avformat/mov: Support multiple thumbnails in HEIF

Prevents ffmpeg/ffprobe from erroring out when reading an HEIF that
contains multiple hvcC thumbnails (e.g. from a Nikon Z6III camera).

Before, move_read_iref_thmb() would always override the stored
thmb_item_id in the MOVContext with each new read thumbnail, causing a
stream and item_id mismatch later in mov_parse_heif_items(), resulting
in the "HEIF thumbnail doesn't reference a stream" error message.

To solve this,

- Turn thmb_item_id into an array of IDs because multiple thumbnails can
  exist
- Change check in mov_parse_heif_items() to compare against all stored
  thumbnail IDs to see if any item missing a stream is in the list of
  thumbnail IDs.

Signed-off-by: Eric Joyner <erj@erj.cc>
Reviewed-by: Lynne <dev@lynne.ee>
Signed-off-by: James Almer <jamrial@gmail.com>

0 files changed, 0 insertions, 0 deletions