Andreas Rheinhardt:
> toq...@gmail.com:
>> From: Wu Jianhua <toq...@outlook.com>
>>
>> Signed-off-by: Wu Jianhua <toq...@outlook.com>
>> ---
>> libavcodec/h274.c | 163 ++++++++++++++++++++++++++++++++++++++++++++++
>> libavcodec/h274.h | 7 ++
>> 2 files changed, 170 insertions(+)
>>
>> diff --git a/libavcodec/h274.c b/libavcodec/h274.c
>> index 5709200322..9edc705042 100644
>> --- a/libavcodec/h274.c
>> +++ b/libavcodec/h274.c
>> @@ -26,7 +26,11 @@
>> */
>>
>> #include "libavutil/avassert.h"
>> +#include "libavutil/bswap.h"
>> +#include "libavutil/crc.h"
>> #include "libavutil/imgutils.h"
>> +#include "libavutil/md5.h"
>> +#include "libavutil/mem.h"
>>
>> #include "h274.h"
>>
>> @@ -790,3 +794,162 @@ static const int8_t R64T[64][64] = {
>> 17, -16, 15, -14, 13, -12, 11, -10, 9, -8, 7, -6, 4,
>> -3, 2, -1,
>> }
>> };
>> +
>> +static int verify_plane_md5(struct AVMD5 *ctx,
>> + const uint8_t *src, const int w, const int h, const int stride,
>> + const uint8_t *expected)
>> +{
>> +#define MD5_SIZE 16
>> + uint8_t md5[MD5_SIZE];
>> + av_md5_init(ctx);
>> + for (int j = 0; j < h; j++) {
>> + av_md5_update(ctx, src, w);
>> + src += stride;
>> + }
>> + av_md5_final(ctx, md5);
>> +
>> + if (memcmp(md5, expected, MD5_SIZE))
>> + return AVERROR_INVALIDDATA;
>> +
>> + return 0;
>> +}
>> +
>> +static int verify_plane_crc(const uint8_t *src, const int w, const int h,
>> const int stride,
>> + const uint8_t *expected)
>> +{
>> + uint32_t crc = 0x0F1D; // CRC-16-CCITT-AUG
>> + const AVCRC *ctx = av_crc_get_table(AV_CRC_16_CCITT);
>> +
>> + for (int j = 0; j < h; j++) {
>> + crc = av_crc(ctx, crc, src, w);
>> + src += stride;
>> + }
>> + crc = av_bswap16(crc);
>> +
>> + if (memcmp(&crc, expected, sizeof(uint16_t)))
>
> This seems endian-dependent (as are the other checks). Why don't you
> simply pass the proper CRC as uint16_t/uint32_t parameter?
>
>> + return AVERROR_INVALIDDATA;
>> +
>> + return 0;
>> +}
>> +
>> +#define CAL_CHECKSUM(pixel) (checksum + ((pixel) ^ xor_mask))
>> +static int verify_plane_checksum(const uint8_t *src, const int w, const int
>> h, const int stride, const int ps,
>> + const uint8_t *expected)
>> +{
>> + uint32_t checksum = 0;
>> +
>> + for (int y = 0; y < h; y++) {
>> + for (int x = 0; x < w; x++) {
>> + const int xor_mask = (x & 0xFF) ^ (y & 0xFF) ^ (x >> 8) ^ (y >>
>> 8);
>> + checksum = CAL_CHECKSUM(src[x << ps]);
>> + if (ps)
>> + checksum = CAL_CHECKSUM(src[(x << ps) + 1]);
>
> Why don't you use checksum += instead of using checksum in the
> CAL_CHECKSUM macro in a hardcoded manner?
>
>> + }
>> + src += stride;
>> + }
>> +
>> + if (checksum != *(uint32_t*)expected)
>> + return AVERROR_INVALIDDATA;
>> +
>> + return 0;
>> +}
>> +
>> +static const uint8_t *get_plane_hash(const H274SEIPictureHash *h, const int
>> plane)
>> +{
>> + if (!h->hash_type)
>> + return h->md5[plane];
>> + if (h->hash_type == 1)
>> + return (uint8_t*)&h->crc[plane];
>> + return (uint8_t*)&h->checksum[plane];
>> +}
>
> This function seems completely useless; you should better pass the
> proper expected value to the functions directly (by value for non-md5).
>
>> +
>> +enum {
>> + HASH_MD5SUM,
>> + HASH_CRC,
>> + HASH_CHECKSUM,
>> + HASH_LAST = HASH_CHECKSUM,
>> +};
>> +
>> +struct H274HashContext {
>> + int type;
>> + struct AVMD5 *ctx;
>> +};
>> +
>> +int ff_h274_hash_freep(H274HashContext **ctx)
>> +{
>> + if (ctx && *ctx) {
>
> Don't check for ctx. Passing a NULL to a freep-function is insane.
>
>> + H274HashContext *c = *ctx;
>> + if (c->ctx)
>> + av_free(c->ctx);
>> + av_freep(ctx);
>> + }
>> + return 0;
>
> Why is this function returning anything?
>
>> +}
>> +
>> +int ff_h274_hash_init(H274HashContext **ctx, const int type)
>> +{
>> + H274HashContext *c;
>> +
>> + if (type > HASH_LAST || !ctx)
>> + return AVERROR(EINVAL);
>> +
>> + c = *ctx;
>> + if (c) {
>> + if (c->type != type) {
>> + if (c->type == HASH_MD5SUM)
>> + av_freep(&c->ctx);
>> + c->type = type;
>> + }
>> + } else {
>> + *ctx = c = av_mallocz(sizeof(H274HashContext));
>
> Why is this separately allocated?
>
>> + if (!c)
>> + return AVERROR(ENOMEM);
>> + c->type = type;
>> + }
>> +
>> + if (type == HASH_MD5SUM && !c->ctx) {
>> + c->ctx = av_md5_alloc();
>> + if (!c->ctx)
>> + return AVERROR(ENOMEM);
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +int ff_h274_hash_verify(H274HashContext *c, const H274SEIPictureHash *hash,
>> + const AVFrame *frame, const int coded_width, const int coded_height)
>> +{
>> + const AVPixFmtDescriptor *desc;
>> + int err = 0;
>> +
>> + if (!c || !hash || !frame)
>> + return AVERROR(EINVAL);
>> +
>> + if (c->type != hash->hash_type)
>> + return AVERROR(EINVAL);
>> +
>> + desc = av_pix_fmt_desc_get(frame->format);
>> + if (!desc)
>> + return AVERROR(EINVAL);
>> +
>> + for (int i = 0; i < desc->nb_components; i++) {
>> + const int w = i ? (coded_width >> desc->log2_chroma_w)
>> : coded_width;
>> + const int h = i ? (coded_height >> desc->log2_chroma_h)
>> : coded_height;
>> + const int ps = desc->comp[i].step - 1;
>> + const uint8_t *expected = get_plane_hash(hash, i);
>> + const uint8_t *src = frame->data[i];
>> + const int stride = frame->linesize[i];
>> +
>> + if (c->type == HASH_MD5SUM)
>> + err = verify_plane_md5(c->ctx, src, w << ps, h, stride,
>> expected);
>> + else if (c->type == HASH_CRC)
>> + err = verify_plane_crc(src, w << ps, h, stride, expected);
>> + else if (c->type == HASH_CHECKSUM)
>> + err = verify_plane_checksum(src, w, h, stride, ps, expected);
>> + if (err < 0)
>> + goto fail;
>> + }
>> +
>> +fail:
>> + return err;
>> +}
>> diff --git a/libavcodec/h274.h b/libavcodec/h274.h
>> index e1803edaf3..e2bb1aec55 100644
>> --- a/libavcodec/h274.h
>> +++ b/libavcodec/h274.h
>> @@ -64,6 +64,8 @@ int ff_h274_apply_film_grain(AVFrame *out, const AVFrame
>> *in,
>> H274FilmGrainDatabase *db,
>> const AVFilmGrainParams *params);
>>
>> +typedef struct H274HashContext H274HashContext;
>> +
>> typedef struct H274SEIPictureHash {
>> int present;
>> union {
>> @@ -74,4 +76,9 @@ typedef struct H274SEIPictureHash {
>> uint8_t hash_type;
>> } H274SEIPictureHash;
>>
>> +int ff_h274_hash_init(H274HashContext **c, int type);
>> +int ff_h274_hash_verify(H274HashContext *c, const H274SEIPictureHash *hash,
>> + const AVFrame *frame, int coded_width, int coded_height);
>> +int ff_h274_hash_freep(H274HashContext **c);
>> +
>> #endif /* AVCODEC_H274_H */
Hi Andreas,
Thanks for your reviews! They help a lot. I've updated the v2
patchset based on your comments. Would you help to review the
v2 patches?
Thanks,
Jianhua
_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
To unsubscribe, visit link above, or email
ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
