FFmpeg: libavcodec/avfft.c Source File

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libavcodec

avfft.c

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1 /*

2 * This file is part of FFmpeg.

3 *

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

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

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

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

8 *

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

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

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

12 * Lesser General Public License for more details.

13 *

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

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

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

17 */

19 #include "libavutil/attributes.h"

20 #include "libavutil/mem.h"

21 #include "avfft.h"

22 #include "fft.h"

23 #include "rdft.h"

24 #include "dct.h"

26 /* FFT */

28 FFTContext *av_fft_init(int nbits, int inverse)

29 {

30 FFTContext *s = av_mallocz(sizeof(*s));

32 if (s && ff_fft_init(s, nbits, inverse))

33 av_freep(&s);

35 return s;

36 }

38 void av_fft_permute(FFTContext *s, FFTComplex *z)

39 {

40 s->fft_permute(s, z);

41 }

43 void av_fft_calc(FFTContext *s, FFTComplex *z)

44 {

45 s->fft_calc(s, z);

46 }

48 av_cold void av_fft_end(FFTContext *s)

49 {

50 if (s) {

51 ff_fft_end(s);

52 av_free(s);

53 }

54 }

56 #if CONFIG_MDCT

58 FFTContext *av_mdct_init(int nbits, int inverse, double scale)

59 {

60 FFTContext *s = av_malloc(sizeof(*s));

62 if (s && ff_mdct_init(s, nbits, inverse, scale))

63 av_freep(&s);

65 return s;

66 }

68 void av_imdct_calc(FFTContext *s, FFTSample *output, const FFTSample *input)

69 {

70 s->imdct_calc(s, output, input);

71 }

73 void av_imdct_half(FFTContext *s, FFTSample *output, const FFTSample *input)

74 {

75 s->imdct_half(s, output, input);

76 }

78 void av_mdct_calc(FFTContext *s, FFTSample *output, const FFTSample *input)

79 {

80 s->mdct_calc(s, output, input);

81 }

83 av_cold void av_mdct_end(FFTContext *s)

84 {

85 if (s) {

86 ff_mdct_end(s);

87 av_free(s);

88 }

89 }

91 #endif /* CONFIG_MDCT */

93 #if CONFIG_RDFT

95 RDFTContext *av_rdft_init(int nbits, enum RDFTransformType trans)

96 {

97 RDFTContext *s = av_malloc(sizeof(*s));

99 if (s && ff_rdft_init(s, nbits, trans))

100 av_freep(&s);

101

102 return s;

103 }

104

105 void av_rdft_calc(RDFTContext *s, FFTSample *data)

106 {

107 s->rdft_calc(s, data);

108 }

109

110 av_cold void av_rdft_end(RDFTContext *s)

111 {

112 if (s) {

113 ff_rdft_end(s);

114 av_free(s);

115 }

116 }

117

118 #endif /* CONFIG_RDFT */

119

120 #if CONFIG_DCT

121

122 DCTContext *av_dct_init(int nbits, enum DCTTransformType inverse)

123 {

124 DCTContext *s = av_malloc(sizeof(*s));

125

126 if (s && ff_dct_init(s, nbits, inverse))

127 av_freep(&s);

128

129 return s;

130 }

131

132 void av_dct_calc(DCTContext *s, FFTSample *data)

133 {

134 s->dct_calc(s, data);

135 }

136

137 av_cold void av_dct_end(DCTContext *s)

138 {

139 if (s) {

140 ff_dct_end(s);

141 av_free(s);

142 }

143 }

144

145 #ifdef TEST

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

147 {

148 int i;

149 #define LEN 1024

150 FFTSample *ref = av_malloc_array(LEN, sizeof(*ref));

151 FFTSample *data = av_malloc_array(LEN, sizeof(*data));

152 RDFTContext *rdft_context = av_rdft_init(10, DFT_R2C);

153 RDFTContext *irdft_context = av_rdft_init(10, IDFT_C2R);

154

155 if (!ref || !data || !rdft_context || !irdft_context)

156 return 2;

157 for (i=0; i<LEN; i++) {

158 ref[i] = data[i] = i*456 + 123 + i*i;

159 }

160 av_rdft_calc(rdft_context, data);

161 av_rdft_calc(irdft_context, data);

162

163 for (i=0; i<LEN; i++) {

164 if (fabs(ref[i] - data[i]/LEN*2) > 1) {

165 fprintf(stderr, "Failed at %d (%f %f)\n", i, ref[i], data[i]/LEN*2);

166 return 1;

167 }

168 }

169

170 av_rdft_end(rdft_context);

171 av_rdft_end(irdft_context);

172 av_free(data);

173 av_free(ref);

174

175 return 0;

176 }

177 #endif

178

179 #endif /* CONFIG_DCT */

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