[FFmpeg-cvslog] avcodec/mjpegenc_common: Don't check luma/chroma matrices unnecessarily

[Andreas Rheinhardt]

ffmpeg | branch: master | Andreas Rheinhardt <andreas.rheinhardt at outlook.com> | Wed Oct  5 18:23:06 2022 +0200| [77adbe28abd2372eee46ed4c07ad737584bfebc9] | committer: Andreas Rheinhardt

avcodec/mjpegenc_common: Don't check luma/chroma matrices unnecessarily

These matrices are only used for MJPEG, not for LJPEG.
So only check them for the former. This is in preparation
for removing said matrices from LJPEG altogether
(i.e. sending NULL matrices).

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=77adbe28abd2372eee46ed4c07ad737584bfebc9
---

 libavcodec/mjpegenc_common.c | 15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/libavcodec/mjpegenc_common.c b/libavcodec/mjpegenc_common.c
index 98c464fc62..0076e94296 100644
--- a/libavcodec/mjpegenc_common.c
+++ b/libavcodec/mjpegenc_common.c
@@ -61,15 +61,13 @@ static void jpeg_table_header(AVCodecContext *avctx, PutBitContext *p,
                               ScanTable *intra_scantable,
                               uint16_t luma_intra_matrix[64],
                               uint16_t chroma_intra_matrix[64],
-                              int hsample[3], int use_slices)
+                              int hsample[3], int use_slices, int matrices_differ)
 {
     int i, j, size;
     uint8_t *ptr;
 
     if (m) {
-        int matrix_count = 1 + !!memcmp(luma_intra_matrix,
-                                        chroma_intra_matrix,
-                                        sizeof(luma_intra_matrix[0]) * 64);
+        int matrix_count = 1 + matrices_differ;
         if (m->force_duplicated_matrix)
             matrix_count = 2;
         /* quant matrixes */
@@ -285,9 +283,7 @@ void ff_mjpeg_encode_picture_header(AVCodecContext *avctx, PutBitContext *pb,
     const int lossless = !m;
     int hsample[4], vsample[4];
     int components = 3 + (avctx->pix_fmt == AV_PIX_FMT_BGRA);
-    int chroma_matrix = !!memcmp(luma_intra_matrix,
-                                 chroma_intra_matrix,
-                                 sizeof(luma_intra_matrix[0])*64);
+    int chroma_matrix;
 
     ff_mjpeg_init_hvsample(avctx, hsample, vsample);
 
@@ -299,9 +295,12 @@ void ff_mjpeg_encode_picture_header(AVCodecContext *avctx, PutBitContext *pb,
 
     jpeg_put_comments(avctx, pb, frame);
 
+    chroma_matrix = !lossless && !!memcmp(luma_intra_matrix,
+                                          chroma_intra_matrix,
+                                          sizeof(luma_intra_matrix[0]) * 64);
     jpeg_table_header(avctx, pb, m, intra_scantable,
                       luma_intra_matrix, chroma_intra_matrix, hsample,
-                      use_slices);
+                      use_slices, chroma_matrix);
 
     switch (avctx->codec_id) {
     case AV_CODEC_ID_MJPEG:  put_marker(pb, SOF0 ); break;