From a9f8587e152c16e943c645ff295e015384ccd76d Mon Sep 17 00:00:00 2001
From: Justin Ruggles <justin.ruggles@gmail.com>
Date: Sun, 14 Sep 2008 21:39:54 +0000
Subject: [PATCH] write MD5 checksum to FLAC header. update regression tests.

Originally committed as revision 15326 to svn://svn.ffmpeg.org/ffmpeg/trunk
---
 libavcodec/flacenc.c          | 30 +++++++++++++++++++++++++++++-
 tests/ffmpeg.regression.ref   |  2 +-
 tests/rotozoom.regression.ref |  2 +-
 3 files changed, 31 insertions(+), 3 deletions(-)

diff --git a/libavcodec/flacenc.c b/libavcodec/flacenc.c
index d1002f3814..bdd4932c2b 100644
--- a/libavcodec/flacenc.c
+++ b/libavcodec/flacenc.c
@@ -21,6 +21,7 @@
 
 #include "libavutil/crc.h"
 #include "libavutil/lls.h"
+#include "libavutil/md5.h"
 #include "avcodec.h"
 #include "bitstream.h"
 #include "dsputil.h"
@@ -97,10 +98,12 @@ typedef struct FlacEncodeContext {
     int max_framesize;
     uint32_t frame_count;
     uint64_t sample_count;
+    uint8_t md5sum[16];
     FlacFrame frame;
     CompressionOptions options;
     AVCodecContext *avctx;
     DSPContext dsp;
+    struct AVMD5 *md5ctx;
 } FlacEncodeContext;
 
 static const int flac_samplerates[16] = {
@@ -139,7 +142,7 @@ static void write_streaminfo(FlacEncodeContext *s, uint8_t *header)
     put_bits(&pb, 24, (s->sample_count & 0xFFFFFF000LL) >> 12);
     put_bits(&pb, 12,  s->sample_count & 0x000000FFFLL);
     flush_put_bits(&pb);
-    /* MD5 signature = 0 */
+    memcpy(&header[18], s->md5sum, 16);
 }
 
 /**
@@ -372,6 +375,12 @@ static av_cold int flac_encode_init(AVCodecContext *avctx)
         s->max_framesize = 14 + (s->avctx->frame_size * s->channels * 2);
     }
 
+    /* initialize MD5 context */
+    s->md5ctx = av_malloc(av_md5_size);
+    if(!s->md5ctx)
+        return AVERROR_NOMEM;
+    av_md5_init(s->md5ctx);
+
     streaminfo = av_malloc(FLAC_STREAMINFO_SIZE);
     write_streaminfo(s, streaminfo);
     avctx->extradata = streaminfo;
@@ -1238,6 +1247,19 @@ static void output_frame_footer(FlacEncodeContext *s)
     flush_put_bits(&s->pb);
 }
 
+static void update_md5_sum(FlacEncodeContext *s, int16_t *samples)
+{
+#ifdef WORDS_BIGENDIAN
+    int i;
+    for(i = 0; i < s->frame.blocksize*s->channels; i++) {
+        int16_t smp = le2me_16(samples[i]);
+        av_md5_update(s->md5ctx, (uint8_t *)&smp, 2);
+    }
+#else
+    av_md5_update(s->md5ctx, (uint8_t *)samples, s->frame.blocksize*s->channels*2);
+#endif
+}
+
 static int flac_encode_frame(AVCodecContext *avctx, uint8_t *frame,
                              int buf_size, void *data)
 {
@@ -1256,6 +1278,7 @@ static int flac_encode_frame(AVCodecContext *avctx, uint8_t *frame,
 
     /* when the last block is reached, update the header in extradata */
     if (!data) {
+        av_md5_final(s->md5ctx, s->md5sum);
         write_streaminfo(s, avctx->extradata);
         return 0;
     }
@@ -1294,12 +1317,17 @@ write_frame:
 
     s->frame_count++;
     s->sample_count += avctx->frame_size;
+    update_md5_sum(s, samples);
 
     return out_bytes;
 }
 
 static av_cold int flac_encode_close(AVCodecContext *avctx)
 {
+    if (avctx->priv_data) {
+        FlacEncodeContext *s = avctx->priv_data;
+        av_freep(&s->md5ctx);
+    }
     av_freep(&avctx->extradata);
     avctx->extradata_size = 0;
     av_freep(&avctx->coded_frame);
diff --git a/tests/ffmpeg.regression.ref b/tests/ffmpeg.regression.ref
index fd050a6887..d1ce98c4ac 100644
--- a/tests/ffmpeg.regression.ref
+++ b/tests/ffmpeg.regression.ref
@@ -201,7 +201,7 @@ de1122d20d56c44cf49f028e25a67788 *./tests/data/a-adpcm_swf.flv
 267073 ./tests/data/a-adpcm_swf.flv
 e48b800e2d9be6afcd430d4f08a34eb6 *./tests/data/adpcm_swf.vsynth.out.wav
 stddev:  934.28 PSNR: 36.91 bytes:  1056812/  1058444
-77c20cb7d6846d6390e0615b7cea7401 *./tests/data/a-flac.flac
+10a8bf5796004b150c7aed115cbafef5 *./tests/data/a-flac.flac
 353368 ./tests/data/a-flac.flac
 95e54b261530a1bcf6de6fe3b21dc5f6 *./tests/data/flac.vsynth.out.wav
 stddev:    0.00 PSNR:999.99 bytes:  1058444/  1058444
diff --git a/tests/rotozoom.regression.ref b/tests/rotozoom.regression.ref
index 470f85d127..dcc4b938d4 100644
--- a/tests/rotozoom.regression.ref
+++ b/tests/rotozoom.regression.ref
@@ -201,7 +201,7 @@ de1122d20d56c44cf49f028e25a67788 *./tests/data/a-adpcm_swf.flv
 267073 ./tests/data/a-adpcm_swf.flv
 e48b800e2d9be6afcd430d4f08a34eb6 *./tests/data/adpcm_swf.rotozoom.out.wav
 stddev:  934.28 PSNR: 36.91 bytes:  1056812/  1058444
-77c20cb7d6846d6390e0615b7cea7401 *./tests/data/a-flac.flac
+10a8bf5796004b150c7aed115cbafef5 *./tests/data/a-flac.flac
 353368 ./tests/data/a-flac.flac
 95e54b261530a1bcf6de6fe3b21dc5f6 *./tests/data/flac.rotozoom.out.wav
 stddev:    0.00 PSNR:999.99 bytes:  1058444/  1058444