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libavutil/samplefmt.c

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00001 /*
00002  * This file is part of FFmpeg.
00003  *
00004  * FFmpeg is free software; you can redistribute it and/or
00005  * modify it under the terms of the GNU Lesser General Public
00006  * License as published by the Free Software Foundation; either
00007  * version 2.1 of the License, or (at your option) any later version.
00008  *
00009  * FFmpeg is distributed in the hope that it will be useful,
00010  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00011  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00012  * Lesser General Public License for more details.
00013  *
00014  * You should have received a copy of the GNU Lesser General Public
00015  * License along with FFmpeg; if not, write to the Free Software
00016  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00017  */
00018 
00019 #include "samplefmt.h"
00020 
00021 #include <stdio.h>
00022 #include <stdlib.h>
00023 #include <string.h>
00024 
00025 typedef struct SampleFmtInfo {
00026     const char *name;
00027     int bits;
00028 } SampleFmtInfo;
00029 
00031 static const SampleFmtInfo sample_fmt_info[AV_SAMPLE_FMT_NB] = {
00032     [AV_SAMPLE_FMT_U8]  = { .name = "u8",  .bits = 8 },
00033     [AV_SAMPLE_FMT_S16] = { .name = "s16", .bits = 16 },
00034     [AV_SAMPLE_FMT_S32] = { .name = "s32", .bits = 32 },
00035     [AV_SAMPLE_FMT_FLT] = { .name = "flt", .bits = 32 },
00036     [AV_SAMPLE_FMT_DBL] = { .name = "dbl", .bits = 64 },
00037 };
00038 
00039 const char *av_get_sample_fmt_name(enum AVSampleFormat sample_fmt)
00040 {
00041     if (sample_fmt < 0 || sample_fmt >= AV_SAMPLE_FMT_NB)
00042         return NULL;
00043     return sample_fmt_info[sample_fmt].name;
00044 }
00045 
00046 enum AVSampleFormat av_get_sample_fmt(const char *name)
00047 {
00048     int i;
00049 
00050     for (i = 0; i < AV_SAMPLE_FMT_NB; i++)
00051         if (!strcmp(sample_fmt_info[i].name, name))
00052             return i;
00053     return AV_SAMPLE_FMT_NONE;
00054 }
00055 
00056 char *av_get_sample_fmt_string (char *buf, int buf_size, enum AVSampleFormat sample_fmt)
00057 {
00058     /* print header */
00059     if (sample_fmt < 0)
00060         snprintf(buf, buf_size, "name  " " depth");
00061     else if (sample_fmt < AV_SAMPLE_FMT_NB) {
00062         SampleFmtInfo info = sample_fmt_info[sample_fmt];
00063         snprintf (buf, buf_size, "%-6s" "   %2d ", info.name, info.bits);
00064     }
00065 
00066     return buf;
00067 }
00068 
00069 int av_get_bytes_per_sample(enum AVSampleFormat sample_fmt)
00070 {
00071      return sample_fmt < 0 || sample_fmt >= AV_SAMPLE_FMT_NB ?
00072         0 : sample_fmt_info[sample_fmt].bits >> 3;
00073 }
00074 
00075 #if FF_API_GET_BITS_PER_SAMPLE_FMT
00076 int av_get_bits_per_sample_fmt(enum AVSampleFormat sample_fmt)
00077 {
00078     return sample_fmt < 0 || sample_fmt >= AV_SAMPLE_FMT_NB ?
00079         0 : sample_fmt_info[sample_fmt].bits;
00080 }
00081 #endif
00082 
00083 int av_samples_fill_arrays(uint8_t *pointers[8], int linesizes[8],
00084                            uint8_t *buf, int nb_channels, int nb_samples,
00085                            enum AVSampleFormat sample_fmt, int planar, int align)
00086 {
00087     int i, linesize;
00088     int sample_size = av_get_bits_per_sample_fmt(sample_fmt) >> 3;
00089 
00090     if (nb_channels * (uint64_t)nb_samples * sample_size >= INT_MAX - align*(uint64_t)nb_channels)
00091         return AVERROR(EINVAL);
00092     linesize = planar ? FFALIGN(nb_samples*sample_size,             align) :
00093                         FFALIGN(nb_samples*sample_size*nb_channels, align);
00094 
00095     if (pointers) {
00096         pointers[0] = buf;
00097         for (i = 1; planar && i < nb_channels; i++) {
00098             pointers[i] = pointers[i-1] + linesize;
00099         }
00100         memset(&pointers[i], 0, (8-i) * sizeof(pointers[0]));
00101     }
00102 
00103     if (linesizes) {
00104         linesizes[0] = linesize;
00105         for (i = 1; planar && i < nb_channels; i++)
00106             linesizes[i] = linesizes[0];
00107         memset(&linesizes[i], 0, (8-i) * sizeof(linesizes[0]));
00108     }
00109 
00110     return planar ? linesize * nb_channels : linesize;
00111 }
00112 
00113 int av_samples_alloc(uint8_t *pointers[8], int linesizes[8],
00114                      int nb_channels, int nb_samples,
00115                      enum AVSampleFormat sample_fmt, int planar,
00116                      int align)
00117 {
00118     uint8_t *buf;
00119     int size = av_samples_fill_arrays(NULL, NULL,
00120                                       NULL, nb_channels, nb_samples,
00121                                       sample_fmt, planar, align);
00122 
00123     buf = av_mallocz(size);
00124     if (!buf)
00125         return AVERROR(ENOMEM);
00126 
00127     return av_samples_fill_arrays(pointers, linesizes,
00128                                   buf, nb_channels, nb_samples,
00129                                   sample_fmt, planar, align);
00130 }

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