FFmpeg: tools/ffhash.c Source File

FFmpeg

[フレーム]

tools

ffhash.c

Go to the documentation of this file.

1 /*

5 *

6 * This file is part of FFmpeg.

7 *

8 * FFmpeg is free software; you can redistribute it and/or

9 * modify it under the terms of the GNU Lesser General Public

10 * License as published by the Free Software Foundation; either

11 * version 2.1 of the License, or (at your option) any later version.

12 *

13 * FFmpeg is distributed in the hope that it will be useful,

14 * but WITHOUT ANY WARRANTY; without even the implied warranty of

15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

16 * Lesser General Public License for more details.

17 *

18 * You should have received a copy of the GNU Lesser General Public

19 * License along with FFmpeg; if not, write to the Free Software

20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

21 */

23 #include "config.h"

24 #include "libavutil/avstring.h"

25 #include "libavutil/error.h"

26 #include "libavutil/hash.h"

28 #include <errno.h>

29 #include <fcntl.h>

30 #include <stdio.h>

31 #include <string.h>

32 #include <sys/stat.h>

34 #if HAVE_IO_H

35 #include <io.h>

36 #endif

37 #if HAVE_UNISTD_H

38 #include <unistd.h>

39 #endif

41 #define SIZE 65536

43 static struct AVHashContext *hash;

44 static int out_b64;

46 static void usage(void)

47 {

48 int i = 0;

49 const char *name;

51 printf("usage: ffhash [b64:]algorithm [input]...\n");

52 printf("Supported hash algorithms:");

53 do {

54 name = av_hash_names(i);

55 if (name)

56 printf(" %s", name);

57 i++;

58 } while(name);

59 printf("\n");

60 }

62 static void finish(void)

63 {

64 char res[2 * AV_HASH_MAX_SIZE + 4];

66 printf("%s=", av_hash_get_name(hash));

67 if (out_b64) {

68 av_hash_final_b64(hash, res, sizeof(res));

69 printf("b64:%s", res);

70 } else {

71 av_hash_final_hex(hash, res, sizeof(res));

72 printf("0x%s", res);

73 }

74 }

76 static int check(char *file)

77 {

78 uint8_t buffer[SIZE];

79 int fd, flags = O_RDONLY;

80 int ret = 0;

82 #ifdef O_BINARY

83 flags |= O_BINARY;

84 #endif

85 if (file) fd = open(file, flags);

86 else fd = 0;

87 if (fd == -1) {

88 printf("%s=OPEN-FAILED: %s:", av_hash_get_name(hash), strerror(errno));

89 ret = 1;

90 goto end;

91 }

93 av_hash_init(hash);

94 for (;;) {

95 int size = read(fd, buffer, SIZE);

96 if (size < 0) {

97 int err = errno;

98 close(fd);

99 finish();

100 printf("+READ-FAILED: %s", strerror(err));

101 ret = 2;

102 goto end;

103 } else if(!size)

104 break;

105 av_hash_update(hash, buffer, size);

106 }

107 close(fd);

108

109 finish();

110 end:

111 if (file)

112 printf(" *%s", file);

113 printf("\n");

114

115 return ret;

116 }

117

118 int main(int argc, char **argv)

119 {

120 int i;

121 int ret = 0;

122 const char *hash_name;

123

124 if (argc == 1) {

125 usage();

126 return 0;

127 }

128

129 hash_name = argv[1];

130 out_b64 = av_strstart(hash_name, "b64:", &hash_name);

131 if ((ret = av_hash_alloc(&hash, hash_name)) < 0) {

132 switch(ret) {

133 case AVERROR(EINVAL):

134 printf("Invalid hash type: %s\n", hash_name);

135 break;

136 case AVERROR(ENOMEM):

137 printf("%s\n", strerror(errno));

138 break;

139 }

140 return 1;

141 }

142

143 for (i = 2; i < argc; i++)

144 ret |= check(argv[i]);

145

146 if (argc < 3)

147 ret |= check(NULL);

148

149 av_hash_freep(&hash);

150

151 return ret;

152 }

flags

const SwsFlags flags[]

Definition: swscale.c:61

name

it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf default minimum maximum flags name is the option name

Definition: writing_filters.txt:88

AVERROR

Filter the word "frame" indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions

printf

__device__ int printf(const char *,...)

AV_HASH_MAX_SIZE

#define AV_HASH_MAX_SIZE

Maximum value that av_hash_get_size() will currently return.

Definition: hash.h:156

av_hash_final_b64

void av_hash_final_b64(struct AVHashContext *ctx, uint8_t *dst, int size)

Finalize a hash context and store the Base64 representation of the actual hash value as a string.

Definition: hash.c:235

finish

static void finish(void)

Definition: ffhash.c:62

static av_cold void close(AVCodecParserContext *s)

Definition: apv_parser.c:135

av_hash_get_name

const char * av_hash_get_name(const AVHashContext *ctx)

Definition: hash.c:104

SIZE

#define SIZE

Definition: ffhash.c:41

av_hash_alloc

int av_hash_alloc(AVHashContext **ctx, const char *name)

Allocate a hash context for the algorithm specified by name.

Definition: hash.c:114

NULL

#define NULL

Definition: coverity.c:32

av_hash_names

const char * av_hash_names(int i)

Get the names of available hash algorithms.

Definition: hash.c:98

av_hash_init

void av_hash_init(AVHashContext *ctx)

Initialize or reset a hash context.

Definition: hash.c:151

usage

static void usage(void)

Definition: ffhash.c:46

av_hash_update

void av_hash_update(AVHashContext *ctx, const uint8_t *src, size_t len)

Update a hash context with additional data.

Definition: hash.c:172

av_hash_freep

void av_hash_freep(AVHashContext **ctx)

Free hash context and set hash context pointer to NULL.

Definition: hash.c:248

error.h

size

int size

Definition: twinvq_data.h:10344

AVHashContext

Definition: hash.c:66

av_strstart

int av_strstart(const char *str, const char *pfx, const char **ptr)

Return non-zero if pfx is a prefix of str.

Definition: avstring.c:36

check

static int check(char *file)

Definition: ffhash.c:76

#define i(width, name, range_min, range_max)

Definition: cbs_h2645.c:256

hash

static struct AVHashContext * hash

Definition: ffhash.c:43

main

int main(int argc, char **argv)

Definition: ffhash.c:118

O_BINARY

#define O_BINARY

ret

Definition: filter_design.txt:187

hash.h

buffer

the frame and frame reference mechanism is intended to as much as expensive copies of that data while still allowing the filters to produce correct results The data is stored in buffers represented by AVFrame structures Several references can point to the same frame buffer

Definition: filter_design.txt:49

av_hash_final_hex

void av_hash_final_hex(struct AVHashContext *ctx, uint8_t *dst, int size)

Finalize a hash context and store the hexadecimal representation of the actual hash value as a string...

Definition: hash.c:225

avstring.h

out_b64

static int out_b64

Definition: ffhash.c:44

read

static uint32_t BS_FUNC() read(BSCTX *bc, unsigned int n)

Return n bits from the buffer, n has to be in the 0-32 range.

Definition: bitstream_template.h:239

Generated on Sat Oct 18 2025 19:23:43 for FFmpeg by doxygen 1.8.17