FFmpeg interface improvements

This patch changes a couple of things in the video output encoding.

{F362527}

- Clearer separation between container and codec. No more "format", as this is
  too ambiguous. As a result, codecs were removed from the container list.
- Added FFmpeg speed presets, so the user can choosen from the range "Very
  slow" to "Ultra fast". By default no preset is used.
- Added Constant Rate Factor (CRF) mode, which allows changing the bit-rate
  depending on the desired quality and the input. This generally produces the
  best quality videos, at the expense of not knowing the exact bit-rate and
  file size.
- Added optional maximum of non-B-frames between B-frames (`max_b_frames`).
- Presets were adjusted for these changes, and new presets added. One of the
  new presets is [recommended](https://trac.ffmpeg.org/wiki/Encode/VFX#H.264)
  for reviewing videos, as it allows players to scrub through it easily. Might
  be nice in weeklies. This preset also requires control over the
  `max_b_frames` setting.

GUI-only changes:
- Renamed "MPEG" in the output file format menu with "FFmpeg", as this is more
  accurate. After all, FFmpeg is used when this option is chosen, which can
  also output non-MPEG files.
- Certain parts of the GUI are disabled when not in use:
    - bit rate options are not used when a constant rate factor is given.
    - audio bitrate & volume are not used when no audio is exported.

Note that I did not touch `BKE_ffmpeg_preset_set()`. There are currently two
preset systems for FFmpeg (`BKE_ffmpeg_preset_set()` and the Python preset
system). Before we do more work on `BKE_ffmpeg_preset_set()`, I think it's a
good idea to determine whether we want to keep it at all.

After this patch has been accepted, I'd be happy to go through the code and
remove any then-obsolete bits, such as the handling of "XVID" as a container
format.

Reviewers: sergey, mont29, brecht

Subscribers: mpan3, Blendify, brecht, fsiddi

Tags: #bf_blender

Differential Revision: https://developer.blender.org/D2242

1 files changed, 37 insertions, 0 deletions

diff --git a/source/blender/makesdna/DNA_scene_types.h b/source/blender/makesdna/DNA_scene_types.h
index 5c5264afcba..94f23197293 100644
--- a/source/blender/makesdna/DNA_scene_types.h
+++ b/source/blender/makesdna/DNA_scene_types.h
@@ -135,6 +135,37 @@ typedef struct QuicktimeCodecSettings {
 	int pad1;
 } QuicktimeCodecSettings;
 
+typedef enum FFMpegPreset {
+	FFM_PRESET_NONE,
+	FFM_PRESET_ULTRAFAST,
+	FFM_PRESET_SUPERFAST,
+	FFM_PRESET_VERYFAST,
+	FFM_PRESET_FASTER,
+	FFM_PRESET_FAST,
+	FFM_PRESET_MEDIUM,
+	FFM_PRESET_SLOW,
+	FFM_PRESET_SLOWER,
+	FFM_PRESET_VERYSLOW,
+} FFMpegPreset;
+
+
+/* Mapping from easily-understandable descriptions to CRF values.
+ * Assumes we output 8-bit video. Needs to be remapped if 10-bit
+ * is output.
+ * We use a slightly wider than "subjectively sane range" according
+ * to https://trac.ffmpeg.org/wiki/Encode/H.264#a1.ChooseaCRFvalue
+ */
+typedef enum FFMpegCrf {
+	FFM_CRF_NONE = -1,
+	FFM_CRF_LOSSLESS = 0,
+	FFM_CRF_PERC_LOSSLESS = 17,
+	FFM_CRF_HIGH = 20,
+	FFM_CRF_MEDIUM = 23,
+	FFM_CRF_LOW = 26,
+	FFM_CRF_VERYLOW = 29,
+	FFM_CRF_LOWEST = 32,
+} FFMpegCrf;
+
 typedef struct FFMpegCodecData {
 	int type;
 	int codec;
@@ -146,13 +177,18 @@ typedef struct FFMpegCodecData {
 	int audio_pad;
 	float audio_volume;
 	int gop_size;
+	int max_b_frames; /* only used if FFMPEG_USE_MAX_B_FRAMES flag is set. */
 	int flags;
+	int constant_rate_factor;
+	int ffmpeg_preset; /* see FFMpegPreset */
 
 	int rc_min_rate;
 	int rc_max_rate;
 	int rc_buffer_size;
 	int mux_packet_size;
 	int mux_rate;
+	int pad1;
+
 	IDProperty *properties;
 } FFMpegCodecData;
 
@@ -1982,6 +2018,7 @@ enum {
 #endif
 	FFMPEG_AUTOSPLIT_OUTPUT = 2,
 	FFMPEG_LOSSLESS_OUTPUT  = 4,
+	FFMPEG_USE_MAX_B_FRAMES = (1 << 3),
 };
 
 /* Paint.flags */