| /* |
| * samplerate conversion for both audio and video |
| * Copyright (c) 2000 Fabrice Bellard |
| * |
| * This file is part of FFmpeg. |
| * |
| * FFmpeg is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either |
| * version 2.1 of the License, or (at your option) any later version. |
| * |
| * FFmpeg is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with FFmpeg; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| |
| /** |
| * @file |
| * samplerate conversion for both audio and video |
| */ |
| |
| #include <string.h> |
| |
| #include "avcodec.h" |
| #include "audioconvert.h" |
| #include "libavutil/opt.h" |
| #include "libavutil/mem.h" |
| #include "libavutil/samplefmt.h" |
| |
| #if FF_API_AVCODEC_RESAMPLE |
| FF_DISABLE_DEPRECATION_WARNINGS |
| |
| #define MAX_CHANNELS 8 |
| |
| struct AVResampleContext; |
| |
| static const char *context_to_name(void *ptr) |
| { |
| return "audioresample"; |
| } |
| |
| static const AVOption options[] = {{NULL}}; |
| static const AVClass audioresample_context_class = { |
| "ReSampleContext", context_to_name, options, LIBAVUTIL_VERSION_INT |
| }; |
| |
| struct ReSampleContext { |
| struct AVResampleContext *resample_context; |
| short *temp[MAX_CHANNELS]; |
| int temp_len; |
| float ratio; |
| /* channel convert */ |
| int input_channels, output_channels, filter_channels; |
| AVAudioConvert *convert_ctx[2]; |
| enum AVSampleFormat sample_fmt[2]; ///< input and output sample format |
| unsigned sample_size[2]; ///< size of one sample in sample_fmt |
| short *buffer[2]; ///< buffers used for conversion to S16 |
| unsigned buffer_size[2]; ///< sizes of allocated buffers |
| }; |
| |
| /* n1: number of samples */ |
| static void stereo_to_mono(short *output, short *input, int n1) |
| { |
| short *p, *q; |
| int n = n1; |
| |
| p = input; |
| q = output; |
| while (n >= 4) { |
| q[0] = (p[0] + p[1]) >> 1; |
| q[1] = (p[2] + p[3]) >> 1; |
| q[2] = (p[4] + p[5]) >> 1; |
| q[3] = (p[6] + p[7]) >> 1; |
| q += 4; |
| p += 8; |
| n -= 4; |
| } |
| while (n > 0) { |
| q[0] = (p[0] + p[1]) >> 1; |
| q++; |
| p += 2; |
| n--; |
| } |
| } |
| |
| /* n1: number of samples */ |
| static void mono_to_stereo(short *output, short *input, int n1) |
| { |
| short *p, *q; |
| int n = n1; |
| int v; |
| |
| p = input; |
| q = output; |
| while (n >= 4) { |
| v = p[0]; q[0] = v; q[1] = v; |
| v = p[1]; q[2] = v; q[3] = v; |
| v = p[2]; q[4] = v; q[5] = v; |
| v = p[3]; q[6] = v; q[7] = v; |
| q += 8; |
| p += 4; |
| n -= 4; |
| } |
| while (n > 0) { |
| v = p[0]; q[0] = v; q[1] = v; |
| q += 2; |
| p += 1; |
| n--; |
| } |
| } |
| |
| /* |
| 5.1 to stereo input: [fl, fr, c, lfe, rl, rr] |
| - Left = front_left + rear_gain * rear_left + center_gain * center |
| - Right = front_right + rear_gain * rear_right + center_gain * center |
| Where rear_gain is usually around 0.5-1.0 and |
| center_gain is almost always 0.7 (-3 dB) |
| */ |
| static void surround_to_stereo(short **output, short *input, int channels, int samples) |
| { |
| int i; |
| short l, r; |
| |
| for (i = 0; i < samples; i++) { |
| int fl,fr,c,rl,rr; |
| fl = input[0]; |
| fr = input[1]; |
| c = input[2]; |
| // lfe = input[3]; |
| rl = input[4]; |
| rr = input[5]; |
| |
| l = av_clip_int16(fl + (0.5 * rl) + (0.7 * c)); |
| r = av_clip_int16(fr + (0.5 * rr) + (0.7 * c)); |
| |
| /* output l & r. */ |
| *output[0]++ = l; |
| *output[1]++ = r; |
| |
| /* increment input. */ |
| input += channels; |
| } |
| } |
| |
| static void deinterleave(short **output, short *input, int channels, int samples) |
| { |
| int i, j; |
| |
| for (i = 0; i < samples; i++) { |
| for (j = 0; j < channels; j++) { |
| *output[j]++ = *input++; |
| } |
| } |
| } |
| |
| static void interleave(short *output, short **input, int channels, int samples) |
| { |
| int i, j; |
| |
| for (i = 0; i < samples; i++) { |
| for (j = 0; j < channels; j++) { |
| *output++ = *input[j]++; |
| } |
| } |
| } |
| |
| static void ac3_5p1_mux(short *output, short *input1, short *input2, int n) |
| { |
| int i; |
| short l, r; |
| |
| for (i = 0; i < n; i++) { |
| l = *input1++; |
| r = *input2++; |
| *output++ = l; /* left */ |
| *output++ = (l / 2) + (r / 2); /* center */ |
| *output++ = r; /* right */ |
| *output++ = 0; /* left surround */ |
| *output++ = 0; /* right surroud */ |
| *output++ = 0; /* low freq */ |
| } |
| } |
| |
| #define SUPPORT_RESAMPLE(ch1, ch2, ch3, ch4, ch5, ch6, ch7, ch8) \ |
| ch8<<7 | ch7<<6 | ch6<<5 | ch5<<4 | ch4<<3 | ch3<<2 | ch2<<1 | ch1<<0 |
| |
| static const uint8_t supported_resampling[MAX_CHANNELS] = { |
| // output ch: 1 2 3 4 5 6 7 8 |
| SUPPORT_RESAMPLE(1, 1, 0, 0, 0, 0, 0, 0), // 1 input channel |
| SUPPORT_RESAMPLE(1, 1, 0, 0, 0, 1, 0, 0), // 2 input channels |
| SUPPORT_RESAMPLE(0, 0, 1, 0, 0, 0, 0, 0), // 3 input channels |
| SUPPORT_RESAMPLE(0, 0, 0, 1, 0, 0, 0, 0), // 4 input channels |
| SUPPORT_RESAMPLE(0, 0, 0, 0, 1, 0, 0, 0), // 5 input channels |
| SUPPORT_RESAMPLE(0, 1, 0, 0, 0, 1, 0, 0), // 6 input channels |
| SUPPORT_RESAMPLE(0, 0, 0, 0, 0, 0, 1, 0), // 7 input channels |
| SUPPORT_RESAMPLE(0, 0, 0, 0, 0, 0, 0, 1), // 8 input channels |
| }; |
| |
| ReSampleContext *av_audio_resample_init(int output_channels, int input_channels, |
| int output_rate, int input_rate, |
| enum AVSampleFormat sample_fmt_out, |
| enum AVSampleFormat sample_fmt_in, |
| int filter_length, int log2_phase_count, |
| int linear, double cutoff) |
| { |
| ReSampleContext *s; |
| |
| if (input_channels > MAX_CHANNELS) { |
| av_log(NULL, AV_LOG_ERROR, |
| "Resampling with input channels greater than %d is unsupported.\n", |
| MAX_CHANNELS); |
| return NULL; |
| } |
| if (!(supported_resampling[input_channels-1] & (1<<(output_channels-1)))) { |
| int i; |
| av_log(NULL, AV_LOG_ERROR, "Unsupported audio resampling. Allowed " |
| "output channels for %d input channel%s", input_channels, |
| input_channels > 1 ? "s:" : ":"); |
| for (i = 0; i < MAX_CHANNELS; i++) |
| if (supported_resampling[input_channels-1] & (1<<i)) |
| av_log(NULL, AV_LOG_ERROR, " %d", i + 1); |
| av_log(NULL, AV_LOG_ERROR, "\n"); |
| return NULL; |
| } |
| |
| s = av_mallocz(sizeof(ReSampleContext)); |
| if (!s) { |
| av_log(NULL, AV_LOG_ERROR, "Can't allocate memory for resample context.\n"); |
| return NULL; |
| } |
| |
| s->ratio = (float)output_rate / (float)input_rate; |
| |
| s->input_channels = input_channels; |
| s->output_channels = output_channels; |
| |
| s->filter_channels = s->input_channels; |
| if (s->output_channels < s->filter_channels) |
| s->filter_channels = s->output_channels; |
| |
| s->sample_fmt[0] = sample_fmt_in; |
| s->sample_fmt[1] = sample_fmt_out; |
| s->sample_size[0] = av_get_bytes_per_sample(s->sample_fmt[0]); |
| s->sample_size[1] = av_get_bytes_per_sample(s->sample_fmt[1]); |
| |
| if (s->sample_fmt[0] != AV_SAMPLE_FMT_S16) { |
| if (!(s->convert_ctx[0] = av_audio_convert_alloc(AV_SAMPLE_FMT_S16, 1, |
| s->sample_fmt[0], 1, NULL, 0))) { |
| av_log(s, AV_LOG_ERROR, |
| "Cannot convert %s sample format to s16 sample format\n", |
| av_get_sample_fmt_name(s->sample_fmt[0])); |
| av_free(s); |
| return NULL; |
| } |
| } |
| |
| if (s->sample_fmt[1] != AV_SAMPLE_FMT_S16) { |
| if (!(s->convert_ctx[1] = av_audio_convert_alloc(s->sample_fmt[1], 1, |
| AV_SAMPLE_FMT_S16, 1, NULL, 0))) { |
| av_log(s, AV_LOG_ERROR, |
| "Cannot convert s16 sample format to %s sample format\n", |
| av_get_sample_fmt_name(s->sample_fmt[1])); |
| av_audio_convert_free(s->convert_ctx[0]); |
| av_free(s); |
| return NULL; |
| } |
| } |
| |
| s->resample_context = av_resample_init(output_rate, input_rate, |
| filter_length, log2_phase_count, |
| linear, cutoff); |
| |
| *(const AVClass**)s->resample_context = &audioresample_context_class; |
| |
| return s; |
| } |
| |
| /* resample audio. 'nb_samples' is the number of input samples */ |
| /* XXX: optimize it ! */ |
| int audio_resample(ReSampleContext *s, short *output, short *input, int nb_samples) |
| { |
| int i, nb_samples1; |
| short *bufin[MAX_CHANNELS]; |
| short *bufout[MAX_CHANNELS]; |
| short *buftmp2[MAX_CHANNELS], *buftmp3[MAX_CHANNELS]; |
| short *output_bak = NULL; |
| int lenout; |
| |
| if (s->input_channels == s->output_channels && s->ratio == 1.0 && 0) { |
| /* nothing to do */ |
| memcpy(output, input, nb_samples * s->input_channels * sizeof(short)); |
| return nb_samples; |
| } |
| |
| if (s->sample_fmt[0] != AV_SAMPLE_FMT_S16) { |
| int istride[1] = { s->sample_size[0] }; |
| int ostride[1] = { 2 }; |
| const void *ibuf[1] = { input }; |
| void *obuf[1]; |
| unsigned input_size = nb_samples * s->input_channels * 2; |
| |
| if (!s->buffer_size[0] || s->buffer_size[0] < input_size) { |
| av_free(s->buffer[0]); |
| s->buffer_size[0] = input_size; |
| s->buffer[0] = av_malloc(s->buffer_size[0]); |
| if (!s->buffer[0]) { |
| av_log(s->resample_context, AV_LOG_ERROR, "Could not allocate buffer\n"); |
| return 0; |
| } |
| } |
| |
| obuf[0] = s->buffer[0]; |
| |
| if (av_audio_convert(s->convert_ctx[0], obuf, ostride, |
| ibuf, istride, nb_samples * s->input_channels) < 0) { |
| av_log(s->resample_context, AV_LOG_ERROR, |
| "Audio sample format conversion failed\n"); |
| return 0; |
| } |
| |
| input = s->buffer[0]; |
| } |
| |
| lenout= 2*s->output_channels*nb_samples * s->ratio + 16; |
| |
| if (s->sample_fmt[1] != AV_SAMPLE_FMT_S16) { |
| int out_size = lenout * av_get_bytes_per_sample(s->sample_fmt[1]) * |
| s->output_channels; |
| output_bak = output; |
| |
| if (!s->buffer_size[1] || s->buffer_size[1] < out_size) { |
| av_free(s->buffer[1]); |
| s->buffer_size[1] = out_size; |
| s->buffer[1] = av_malloc(s->buffer_size[1]); |
| if (!s->buffer[1]) { |
| av_log(s->resample_context, AV_LOG_ERROR, "Could not allocate buffer\n"); |
| return 0; |
| } |
| } |
| |
| output = s->buffer[1]; |
| } |
| |
| /* XXX: move those malloc to resample init code */ |
| for (i = 0; i < s->filter_channels; i++) { |
| bufin[i] = av_malloc_array((nb_samples + s->temp_len), sizeof(short)); |
| bufout[i] = av_malloc_array(lenout, sizeof(short)); |
| |
| if (!bufin[i] || !bufout[i]) { |
| av_log(s->resample_context, AV_LOG_ERROR, "Could not allocate buffer\n"); |
| nb_samples1 = 0; |
| goto fail; |
| } |
| |
| memcpy(bufin[i], s->temp[i], s->temp_len * sizeof(short)); |
| buftmp2[i] = bufin[i] + s->temp_len; |
| } |
| |
| if (s->input_channels == 2 && s->output_channels == 1) { |
| buftmp3[0] = output; |
| stereo_to_mono(buftmp2[0], input, nb_samples); |
| } else if (s->output_channels >= 2 && s->input_channels == 1) { |
| buftmp3[0] = bufout[0]; |
| memcpy(buftmp2[0], input, nb_samples * sizeof(short)); |
| } else if (s->input_channels == 6 && s->output_channels ==2) { |
| buftmp3[0] = bufout[0]; |
| buftmp3[1] = bufout[1]; |
| surround_to_stereo(buftmp2, input, s->input_channels, nb_samples); |
| } else if (s->output_channels >= s->input_channels && s->input_channels >= 2) { |
| for (i = 0; i < s->input_channels; i++) { |
| buftmp3[i] = bufout[i]; |
| } |
| deinterleave(buftmp2, input, s->input_channels, nb_samples); |
| } else { |
| buftmp3[0] = output; |
| memcpy(buftmp2[0], input, nb_samples * sizeof(short)); |
| } |
| |
| nb_samples += s->temp_len; |
| |
| /* resample each channel */ |
| nb_samples1 = 0; /* avoid warning */ |
| for (i = 0; i < s->filter_channels; i++) { |
| int consumed; |
| int is_last = i + 1 == s->filter_channels; |
| |
| nb_samples1 = av_resample(s->resample_context, buftmp3[i], bufin[i], |
| &consumed, nb_samples, lenout, is_last); |
| s->temp_len = nb_samples - consumed; |
| s->temp[i] = av_realloc_array(s->temp[i], s->temp_len, sizeof(short)); |
| memcpy(s->temp[i], bufin[i] + consumed, s->temp_len * sizeof(short)); |
| } |
| |
| if (s->output_channels == 2 && s->input_channels == 1) { |
| mono_to_stereo(output, buftmp3[0], nb_samples1); |
| } else if (s->output_channels == 6 && s->input_channels == 2) { |
| ac3_5p1_mux(output, buftmp3[0], buftmp3[1], nb_samples1); |
| } else if ((s->output_channels == s->input_channels && s->input_channels >= 2) || |
| (s->output_channels == 2 && s->input_channels == 6)) { |
| interleave(output, buftmp3, s->output_channels, nb_samples1); |
| } |
| |
| if (s->sample_fmt[1] != AV_SAMPLE_FMT_S16) { |
| int istride[1] = { 2 }; |
| int ostride[1] = { s->sample_size[1] }; |
| const void *ibuf[1] = { output }; |
| void *obuf[1] = { output_bak }; |
| |
| if (av_audio_convert(s->convert_ctx[1], obuf, ostride, |
| ibuf, istride, nb_samples1 * s->output_channels) < 0) { |
| av_log(s->resample_context, AV_LOG_ERROR, |
| "Audio sample format conversion failed\n"); |
| return 0; |
| } |
| } |
| |
| fail: |
| for (i = 0; i < s->filter_channels; i++) { |
| av_free(bufin[i]); |
| av_free(bufout[i]); |
| } |
| |
| return nb_samples1; |
| } |
| |
| void audio_resample_close(ReSampleContext *s) |
| { |
| int i; |
| av_resample_close(s->resample_context); |
| for (i = 0; i < s->filter_channels; i++) |
| av_freep(&s->temp[i]); |
| av_freep(&s->buffer[0]); |
| av_freep(&s->buffer[1]); |
| av_audio_convert_free(s->convert_ctx[0]); |
| av_audio_convert_free(s->convert_ctx[1]); |
| av_free(s); |
| } |
| |
| FF_ENABLE_DEPRECATION_WARNINGS |
| #endif |