picture_pool: add dynamic pools support for opaque pictures

A better solution than the hack done in !6420 (8a31e7c0)

avcodec internal is often allocating more hw pics than what we configure. Even our va modules do allocate more pictures (cf. d3dv11).

This will avoid a deadlock when avcodec use more frames than us.

NB: The pool private data could be allocated in picture_pool instead of using picture private data (but it requires an extra malloc per picture).

changed milestone to %4.0

added Component::Decoders Hw label

On top of !6420 (merged)

added 5 commits

• 2b9dd350 - picture_pool: use a vlc_list
• 0d1d879d - picture_pool: increase POOL_MAX
• e767019a - picture_pool: add a dynamic option
• bc10d037 - decoder: use a dynamic pool for hw decoders
• f07a2349 - avcodec: video: remove i_extra_picture_buffers hack

Compare with previous version

added 3 commits

• cc7e682e - picture_pool: add a dynamic option
• a94c0bef - decoder: use a dynamic pool for hw decoders
• 9305315f - avcodec: video: remove i_extra_picture_buffers hack

Compare with previous version

added MRStatus::NotCompliant label

added 6 commits

• 4e99025d - TMP: avcodec: vaapi: fix AV1
• e4022cae - picture_pool: use a vlc_list
• 6e470c86 - picture_pool: increase POOL_MAX
• 5f3a26e3 - picture_pool: add a dynamic option
• 3a0dbcaf - decoder: use a dynamic pool for hw decoders
• 1b7d8ece - avcodec: video: remove i_extra_picture_buffers hack

Compare with previous version

mentioned in merge request !6420 (merged)

added 6 commits

• 602336c4 - TMP: avcodec: vaapi: fix AV1
• 2335ca30 - picture_pool: use a vlc_list
• 392e942c - picture_pool: increase POOL_MAX
• 64002592 - picture_pool: add a dynamic option
• bd04c86e - decoder: use a dynamic pool for hw decoders
• 1d8b2380 - avcodec: video: remove i_extra_picture_buffers hack

Compare with previous version

added MRStatus::Reviewable label and removed MRStatus::NotCompliant label

added 4 commits

• 8341da1a - picture_pool: use a vlc_list
• bd768b86 - picture_pool: increase POOL_MAX
• 87549c5c - picture_pool: add a dynamic option
• a0e74f62 - decoder: use a dynamic pool for hw decoders

Compare with previous version

resolved all threads

changed the description

Updated to no depend on !6420 (merged)

approved this merge request

Tested on Windows successfully.

added MRStatus::Acceptable label and removed MRStatus::Reviewable label

This will avoid a deadlock when avcodec use more frames than us.

This is dangerous, we will not notice when the pool keeps growing unless we end up with no memory. We should try as much as possible to match what lavc is requesting (including fixing potential bugs).

added MRStatus::InReview label and removed MRStatus::Acceptable label