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<div> {
.name = "Data format",
.priv = &output_format,
.max = 5,
.update = output_format_update,
.choices = CHOICES(
"14-bit",
"12-bit",
"10-bit",
"14-bit lossless",
"12-bit lossless",
"11...8-bit lossless",
),
.help = "Choose the output format (bit depth, compression) for the raw stream:",
.help2 = "14-bit: native uncompressed format used in Canon firmware.\n"
"12-bit: uncompressed, 2 LSB trimmed (nearly lossless on current sensor).\n"
"10-bit: uncompressed, 4 LSB trimmed (small loss of detail in shadows).\n"
"14-bit compressed with Canon's Lossless JPEG. Recommended ISO < 100.\n"
"Signal divided by 4 before compression. Recommended ISO 100-1600.\n"
"Signal divided by 8/16/32/64 before compression, depending on ISO.\n"
},</div>

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/**
* RAW recording. Similar to lv_rec, with some different internals:
*
* - buffering strategy:
* - group the frames in contiguous chunks, up to 32MB, to maximize writing speed
* (speed profile depends on buffer size: http://www.magiclantern.fm/forum/index.php?topic=5471 )
* - always write if there's something to write, even if that means using a small buffer
* (this minimizes idle time for the writing task, keeps memory free in the startup phase,
* and has no impact on the sustained write speeds
* - always choose the largest unused chunk => this maximizes the sustained writing speed
* (small chunks will only be used in extreme situations, to squeeze the last few frames)
* - use any memory chunks that can contain at least one video frame
* (they will only be used when recording is about to stop, so no negative impact in sustained write speed)
*
* - edmac_copy_rectangle: we can crop the image and trim the black borders!
* - edmac operation done outside the LV task (in background, synchronized)
* - on buffer overflow, it stops or skips frames (user-selected)
* - using generic raw routines, no hardcoded stuff (should be easier to port)
* - only for RAW in a single file (do one thing and do it well)
* - goal #1: 1920x1080 on 1000x cards (achieved and exceeded, reports say 1920x1280 continuous!)
* - goal #2: maximize number of frames for any given resolution + buffer + card speed configuration
* (see buffering strategy; I believe it's close to optimal, though I have no idea how to write a mathematical proof for it)
*/
/*
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the
* Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/

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