[FFmpeg-cvslog] lavc, lavu: move frame cropping to a convenience function
wm4
git at videolan.org
Wed Nov 8 18:55:38 EET 2017
ffmpeg | branch: master | wm4 <nfxjfg at googlemail.com> | Sat Jul 22 23:05:13 2017 +0200| [47399ccdfd93d337c96c76fbf591f0e3637131ef] | committer: Anton Khirnov
lavc, lavu: move frame cropping to a convenience function
Signed-off-by: Anton Khirnov <anton at khirnov.net>
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=47399ccdfd93d337c96c76fbf591f0e3637131ef
---
doc/APIchanges | 3 ++
libavcodec/decode.c | 89 ++--------------------------------------------
libavutil/frame.c | 100 ++++++++++++++++++++++++++++++++++++++++++++++++++++
libavutil/frame.h | 34 ++++++++++++++++++
libavutil/version.h | 2 +-
5 files changed, 140 insertions(+), 88 deletions(-)
diff --git a/doc/APIchanges b/doc/APIchanges
index 0f7c839573..30a8f809d1 100644
--- a/doc/APIchanges
+++ b/doc/APIchanges
@@ -13,6 +13,9 @@ libavutil: 2017-03-23
API changes, most recent first:
+2017-xx-xx - xxxxxxx - lavu 56.3.0 - frame.h
+ Add av_frame_apply_cropping().
+
2017-xx-xx - xxxxxxx - lavc 58.4.0 - avcodec.h
DXVA2 and D3D11 hardware accelerated decoding now supports the new hwaccel API,
which can create the decoder context and allocate hardware frame automatically.
diff --git a/libavcodec/decode.c b/libavcodec/decode.c
index 175a6fae4c..9644e89f48 100644
--- a/libavcodec/decode.c
+++ b/libavcodec/decode.c
@@ -446,44 +446,8 @@ int attribute_align_arg avcodec_send_packet(AVCodecContext *avctx, const AVPacke
return 0;
}
-static int calc_cropping_offsets(size_t offsets[4], const AVFrame *frame,
- const AVPixFmtDescriptor *desc)
-{
- int i, j;
-
- for (i = 0; frame->data[i]; i++) {
- const AVComponentDescriptor *comp = NULL;
- int shift_x = (i == 1 || i == 2) ? desc->log2_chroma_w : 0;
- int shift_y = (i == 1 || i == 2) ? desc->log2_chroma_h : 0;
-
- if (desc->flags & (AV_PIX_FMT_FLAG_PAL | AV_PIX_FMT_FLAG_PSEUDOPAL) && i == 1) {
- offsets[i] = 0;
- break;
- }
-
- /* find any component descriptor for this plane */
- for (j = 0; j < desc->nb_components; j++) {
- if (desc->comp[j].plane == i) {
- comp = &desc->comp[j];
- break;
- }
- }
- if (!comp)
- return AVERROR_BUG;
-
- offsets[i] = (frame->crop_top >> shift_y) * frame->linesize[i] +
- (frame->crop_left >> shift_x) * comp->step;
- }
-
- return 0;
-}
-
static int apply_cropping(AVCodecContext *avctx, AVFrame *frame)
{
- const AVPixFmtDescriptor *desc;
- size_t offsets[4];
- int i;
-
/* make sure we are noisy about decoders returning invalid cropping data */
if (frame->crop_left >= INT_MAX - frame->crop_right ||
frame->crop_top >= INT_MAX - frame->crop_bottom ||
@@ -504,57 +468,8 @@ static int apply_cropping(AVCodecContext *avctx, AVFrame *frame)
if (!avctx->apply_cropping)
return 0;
- desc = av_pix_fmt_desc_get(frame->format);
- if (!desc)
- return AVERROR_BUG;
-
- /* Apply just the right/bottom cropping for hwaccel formats. Bitstream
- * formats cannot be easily handled here either (and corresponding decoders
- * should not export any cropping anyway), so do the same for those as well.
- * */
- if (desc->flags & (AV_PIX_FMT_FLAG_BITSTREAM | AV_PIX_FMT_FLAG_HWACCEL)) {
- frame->width -= frame->crop_right;
- frame->height -= frame->crop_bottom;
- frame->crop_right = 0;
- frame->crop_bottom = 0;
- return 0;
- }
-
- /* calculate the offsets for each plane */
- calc_cropping_offsets(offsets, frame, desc);
-
- /* adjust the offsets to avoid breaking alignment */
- if (!(avctx->flags & AV_CODEC_FLAG_UNALIGNED)) {
- int log2_crop_align = frame->crop_left ? av_ctz(frame->crop_left) : INT_MAX;
- int min_log2_align = INT_MAX;
-
- for (i = 0; frame->data[i]; i++) {
- int log2_align = offsets[i] ? av_ctz(offsets[i]) : INT_MAX;
- min_log2_align = FFMIN(log2_align, min_log2_align);
- }
-
- /* we assume, and it should always be true, that the data alignment is
- * related to the cropping alignment by a constant power-of-2 factor */
- if (log2_crop_align < min_log2_align)
- return AVERROR_BUG;
-
- if (min_log2_align < 5) {
- frame->crop_left &= ~((1 << (5 + log2_crop_align - min_log2_align)) - 1);
- calc_cropping_offsets(offsets, frame, desc);
- }
- }
-
- for (i = 0; frame->data[i]; i++)
- frame->data[i] += offsets[i];
-
- frame->width -= (frame->crop_left + frame->crop_right);
- frame->height -= (frame->crop_top + frame->crop_bottom);
- frame->crop_left = 0;
- frame->crop_right = 0;
- frame->crop_top = 0;
- frame->crop_bottom = 0;
-
- return 0;
+ return av_frame_apply_cropping(frame, avctx->flags & AV_CODEC_FLAG_UNALIGNED ?
+ AV_FRAME_CROP_UNALIGNED : 0);
}
int attribute_align_arg avcodec_receive_frame(AVCodecContext *avctx, AVFrame *frame)
diff --git a/libavutil/frame.c b/libavutil/frame.c
index 9cd5f9ab37..db3897c299 100644
--- a/libavutil/frame.c
+++ b/libavutil/frame.c
@@ -596,3 +596,103 @@ void av_frame_remove_side_data(AVFrame *frame, enum AVFrameSideDataType type)
}
}
}
+
+static int calc_cropping_offsets(size_t offsets[4], const AVFrame *frame,
+ const AVPixFmtDescriptor *desc)
+{
+ int i, j;
+
+ for (i = 0; frame->data[i]; i++) {
+ const AVComponentDescriptor *comp = NULL;
+ int shift_x = (i == 1 || i == 2) ? desc->log2_chroma_w : 0;
+ int shift_y = (i == 1 || i == 2) ? desc->log2_chroma_h : 0;
+
+ if (desc->flags & (AV_PIX_FMT_FLAG_PAL | AV_PIX_FMT_FLAG_PSEUDOPAL) && i == 1) {
+ offsets[i] = 0;
+ break;
+ }
+
+ /* find any component descriptor for this plane */
+ for (j = 0; j < desc->nb_components; j++) {
+ if (desc->comp[j].plane == i) {
+ comp = &desc->comp[j];
+ break;
+ }
+ }
+ if (!comp)
+ return AVERROR_BUG;
+
+ offsets[i] = (frame->crop_top >> shift_y) * frame->linesize[i] +
+ (frame->crop_left >> shift_x) * comp->step;
+ }
+
+ return 0;
+}
+
+int av_frame_apply_cropping(AVFrame *frame, int flags)
+{
+ const AVPixFmtDescriptor *desc;
+ size_t offsets[4];
+ int i;
+
+ if (!(frame->width > 0 && frame->height > 0))
+ return AVERROR(EINVAL);
+
+ if (frame->crop_left >= INT_MAX - frame->crop_right ||
+ frame->crop_top >= INT_MAX - frame->crop_bottom ||
+ (frame->crop_left + frame->crop_right) >= frame->width ||
+ (frame->crop_top + frame->crop_bottom) >= frame->height)
+ return AVERROR(ERANGE);
+
+ desc = av_pix_fmt_desc_get(frame->format);
+ if (!desc)
+ return AVERROR_BUG;
+
+ /* Apply just the right/bottom cropping for hwaccel formats. Bitstream
+ * formats cannot be easily handled here either (and corresponding decoders
+ * should not export any cropping anyway), so do the same for those as well.
+ * */
+ if (desc->flags & (AV_PIX_FMT_FLAG_BITSTREAM | AV_PIX_FMT_FLAG_HWACCEL)) {
+ frame->width -= frame->crop_right;
+ frame->height -= frame->crop_bottom;
+ frame->crop_right = 0;
+ frame->crop_bottom = 0;
+ return 0;
+ }
+
+ /* calculate the offsets for each plane */
+ calc_cropping_offsets(offsets, frame, desc);
+
+ /* adjust the offsets to avoid breaking alignment */
+ if (!(flags & AV_FRAME_CROP_UNALIGNED)) {
+ int log2_crop_align = frame->crop_left ? av_ctz(frame->crop_left) : INT_MAX;
+ int min_log2_align = INT_MAX;
+
+ for (i = 0; frame->data[i]; i++) {
+ int log2_align = offsets[i] ? av_ctz(offsets[i]) : INT_MAX;
+ min_log2_align = FFMIN(log2_align, min_log2_align);
+ }
+
+ /* we assume, and it should always be true, that the data alignment is
+ * related to the cropping alignment by a constant power-of-2 factor */
+ if (log2_crop_align < min_log2_align)
+ return AVERROR_BUG;
+
+ if (min_log2_align < 5) {
+ frame->crop_left &= ~((1 << (5 + log2_crop_align - min_log2_align)) - 1);
+ calc_cropping_offsets(offsets, frame, desc);
+ }
+ }
+
+ for (i = 0; frame->data[i]; i++)
+ frame->data[i] += offsets[i];
+
+ frame->width -= (frame->crop_left + frame->crop_right);
+ frame->height -= (frame->crop_top + frame->crop_bottom);
+ frame->crop_left = 0;
+ frame->crop_right = 0;
+ frame->crop_top = 0;
+ frame->crop_bottom = 0;
+
+ return 0;
+}
diff --git a/libavutil/frame.h b/libavutil/frame.h
index f9ffb5bbbf..ff3fe46dd6 100644
--- a/libavutil/frame.h
+++ b/libavutil/frame.h
@@ -580,6 +580,40 @@ AVFrameSideData *av_frame_get_side_data(const AVFrame *frame,
*/
void av_frame_remove_side_data(AVFrame *frame, enum AVFrameSideDataType type);
+
+/**
+ * Flags for frame cropping.
+ */
+enum {
+ /**
+ * Apply the maximum possible cropping, even if it requires setting the
+ * AVFrame.data[] entries to unaligned pointers. Passing unaligned data
+ * to Libav API is generally not allowed, and causes undefined behavior
+ * (such as crashes). You can pass unaligned data only to Libav APIs that
+ * are explicitly documented to accept it. Use this flag only if you
+ * absolutely know what you are doing.
+ */
+ AV_FRAME_CROP_UNALIGNED = 1 << 0,
+};
+
+/**
+ * Crop the given video AVFrame according to its crop_left/crop_top/crop_right/
+ * crop_bottom fields. If cropping is successful, the function will adjust the
+ * data pointers and the width/height fields, and set the crop fields to 0.
+ *
+ * In all cases, the cropping boundaries will be rounded to the inherent
+ * alignment of the pixel format. In some cases, such as for opaque hwaccel
+ * formats, the left/top cropping is ignored. The crop fields are set to 0 even
+ * if the cropping was rounded or ignored.
+ *
+ * @param frame the frame which should be cropped
+ * @param flags Some combination of AV_FRAME_CROP_* flags, or 0.
+ *
+ * @return >= 0 on success, a negative AVERROR on error. If the cropping fields
+ * were invalid, AVERROR(ERANGE) is returned, and nothing is changed.
+ */
+int av_frame_apply_cropping(AVFrame *frame, int flags);
+
/**
* @}
*/
diff --git a/libavutil/version.h b/libavutil/version.h
index 2c85120b64..53bf72efdd 100644
--- a/libavutil/version.h
+++ b/libavutil/version.h
@@ -54,7 +54,7 @@
*/
#define LIBAVUTIL_VERSION_MAJOR 56
-#define LIBAVUTIL_VERSION_MINOR 2
+#define LIBAVUTIL_VERSION_MINOR 3
#define LIBAVUTIL_VERSION_MICRO 0
#define LIBAVUTIL_VERSION_INT AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \
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