[FFmpeg-soc] [soc] libavsequencer [PATCH 06/08] Instrument sample handling public API header file.

[Vitor Sessak]

On 08/13/2010 10:43 PM, Sebastian Vater wrote:
> Vitor Sessak a écrit :
>> On 08/07/2010 09:56 PM, Sebastian Vater wrote:
>>> Sebastian Vater a écrit :
>>>> Updated patch.
>>>>
>>>>
>>>
>>> Hi I have excellent news!
>>>
>>> libavsequencer now flawlessly integrates into FFmpeg, just check out my
>>> latest git. Please do a git pull --rebase, Stefano had problems without
>>> using it.
>>>
>>> Here are the sample.[ch] part of the BSS to review.
>>>
>>> This version compiles perfectly.
>>
>>
>>> sample.h_20100807.patch
>>>
>>> diff --git a/libavsequencer/sample.h b/libavsequencer/sample.h
>>> new file mode 100755
>>> index 0000000..2da365f
>>> --- /dev/null
>>> +++ b/libavsequencer/sample.h
>>> @@ -0,0 +1,302 @@
>>> +/*
>>> + * AVSequencer samples management
>>> + * Copyright (c) 2010 Sebastian Vater<cdgs.basty at googlemail.com>
>>> + *
>>> + * 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
>>> + */
>>> +
>>> +#ifndef AVSEQUENCER_SAMPLE_H
>>> +#define AVSEQUENCER_SAMPLE_H
>>> +
>>> +#include "libavutil/log.h"
>>> +#include "libavformat/avformat.h"
>>> +#include "libavsequencer/synth.h"
>>> +
>>> +/** AVSequencerSample->compat_flags bitfield.  */
>>> +enum AVSequencerSampleCompatFlags {
>>> +    AVSEQ_SAMPLE_COMPAT_FLAG_AFFECT_CHANNEL_PAN     = 0x01, ///<
>>> Sample panning affects channel panning (IT compatibility)
>>> +    AVSEQ_SAMPLE_COMPAT_FLAG_VOLUME_ONLY            = 0x02, ///<  If
>>> a note without a sample is played, only the sample volume will be
>>> left unchanged
>>> +    AVSEQ_SAMPLE_COMPAT_FLAG_START_TONE_PORTAMENTO  = 0x04, ///<  If
>>> a tone portamento with a note is executed but no note is currently
>>> played, the tone portamento will be ignored and start playing the
>>> note normally
>>> +    AVSEQ_SAMPLE_COMPAT_FLAG_PLAY_BEGIN_TONE_PORTA  = 0x08, ///<  If
>>> you change a sample within a tone portamento the sample will be
>>> played from beginning
>>> +};
>>> +
>>> +/** AVSequencerSample->flags bitfield.  */
>>> +enum AVSequencerSampleFlags {
>>> +    AVSEQ_SAMPLE_FLAG_REDIRECT          = 0x01, ///<  Sample is a
>>> redirection (symbolic link)
>>> +    AVSEQ_SAMPLE_FLAG_LOOP              = 0x02, ///<  Use normal loop
>>> points
>>> +    AVSEQ_SAMPLE_FLAG_SUSTAIN_LOOP      = 0x04, ///<  Use sustain
>>> loop points
>>> +    AVSEQ_SAMPLE_FLAG_SAMPLE_PANNING    = 0x08, ///<  Use sample panning
>>> +    AVSEQ_SAMPLE_FLAG_SURROUND_PANNING  = 0x10, ///<  Sample panning
>>> is surround panning
>>> +    AVSEQ_SAMPLE_FLAG_REVERSE           = 0x40, ///<  Sample will be
>>> initially played backwards
>>> +};
>>> +
>>> +/** AVSequencerSample->repeat_mode bitfield.  */
>>> +enum AVSequencerSampleRepMode {
>>> +    AVSEQ_SAMPLE_REP_MODE_BACKWARDS = 0x01, ///<  Use always backward
>>> instead of always forward loop
>>> +    AVSEQ_SAMPLE_REP_MODE_PINGPONG  = 0x02, ///<  Use ping-pong loop
>>> mode, i.e. forward<->  backward
>>> +};
>>> +
>>> +/** AVSequencerSample->sustain_repeat_mode bitfield.  */
>>> +enum AVSequencerSampleSustainRepMode {
>>> +    AVSEQ_SAMPLE_SUSTAIN_REP_MODE_BACKWARDS = 0x01, ///<  Use always
>>> backward instead of always forward loop
>>> +    AVSEQ_SAMPLE_SUSTAIN_REP_MODE_PINGPONG  = 0x02, ///<  Use
>>> ping-pong loop mode, i.e. forward<->  backward
>>> +};
>>> +
>>> +/** AVSequencerSample->env_usage_flags bitfield.  */
>>> +enum AVSequencerSampleEnvUsageFlags {
>>> +    AVSEQ_SAMPLE_FLAG_USE_AUTO_VIBRATO_ENV  = 0x01, ///<  Use
>>> (reload) auto vibrato envelope
>>> +    AVSEQ_SAMPLE_FLAG_USE_AUTO_TREMOLO_ENV  = 0x02, ///<  Use
>>> (reload) auto tremolo envelope
>>> +    AVSEQ_SAMPLE_FLAG_USE_AUTO_PANNOLO_ENV  = 0x04, ///<  Use
>>> (reload) auto pannolo envelope
>>> +};
>>> +
>>> +/** AVSequencerSample->env_proc_flags bitfield.  */
>>> +enum AVSequencerSampleEnvProcFlags {
>>> +    AVSEQ_SAMPLE_FLAG_PROC_AUTO_VIBRATO_ENV = 0x01, ///<  Add first,
>>> then get auto vibrato envelope value
>>> +    AVSEQ_SAMPLE_FLAG_PROC_AUTO_TREMOLO_ENV = 0x02, ///<  Add first,
>>> then get auto tremolo envelope value
>>> +    AVSEQ_SAMPLE_FLAG_PROC_AUTO_PANNOLO_ENV = 0x04, ///<  Add first,
>>> then get auto pannolo envelope value
>>> +    AVSEQ_SAMPLE_FLAG_PROC_LINEAR_AUTO_VIB  = 0x80, ///<  Use linear
>>> frequency table for auto vibrato
>>> +};
>>> +
>>> +/** AVSequencerSample->env_retrig_flags bitfield.  */
>>> +enum AVSequencerSampleEnvRetrigFlags {
>>> +    AVSEQ_SAMPLE_FLAG_RETRIG_AUTO_VIBRATO_ENV   = 0x01, ///<  Not
>>> retrigger auto vibrato envelope
>>> +    AVSEQ_SAMPLE_FLAG_RETRIG_AUTO_TREMOLO_ENV   = 0x02, ///<  Not
>>> retrigger auto tremolo envelope
>>> +    AVSEQ_SAMPLE_FLAG_RETRIG_AUTO_PANNOLO_ENV   = 0x04, ///<  Not
>>> retrigger auto pannolo envelope
>>> +};
>>> +
>>> +/** AVSequencerSample->env_random_flags bitfield.  */
>>> +enum AVSequencerSampleEnvRandomFlags {
>>> +    AVSEQ_SAMPLE_FLAG_RANDOM_AUTO_VIBRATO_ENV   = 0x01, ///<
>>> Randomize auto vibrato envelope
>>> +    AVSEQ_SAMPLE_FLAG_RANDOM_AUTO_TREMOLO_ENV   = 0x02, ///<
>>> Randomize auto tremolo envelope
>>> +    AVSEQ_SAMPLE_FLAG_RANDOM_AUTO_PANNOLO_ENV   = 0x04, ///<
>>> Randomize auto pannolo envelope
>>> +};
>>> +
>>> +/**
>>> + * Sample structure used by all instruments which are either
>>> + * have samples attached or are hybrids.
>>> + * New fields can be added to the end with minor version bumps.
>>> + * Removal, reordering and changes to existing fields require a major
>>> + * version bump.
>>> + */
>>> +typedef struct AVSequencerSample {
>>> +    /**
>>> +     * information on struct for av_log
>>> +     * - set by avseq_alloc_context
>>> +     */
>>> +    const AVClass *av_class;
>>> +
>>> +    /** Metadata information: Original sample file name, sample name,
>>> +     *  artist and comment.  */
>>> +    AVMetadata *metadata;
>>> +
>>> +    /** AVSequencerSynth pointer to synth sound structure or NULL
>>> +       if this is neither a synth nor a hybrid.  */
>>> +    AVSequencerSynth *synth;
>>
>>> +    /** Pointer to raw sample data, must be padded for
>>> +       perfect perfomance gain when accessing sample data.
>>
>> ? Padded with how many bytes? What do you mean with "perfect
>> performance gain"?
>
> As anything else in FFmpeg which is considered to be run by MMX/etc.
> optimized code. Thought, that would be clear.

Just request it to be aligned, should be enough.

>>> +       This can be NULL in case if this is a MIDI instrument
>>> +       or a synth sound instead.  */
>>> +    int16_t *data;
>>
>>
>>> +    /** Number of bytes the raw sample data occupies. 0 for
>>> +       MIDI instruments and synth sounds.  */
>>> +    uint32_t size;
>>> +
>>> +    /** Number of samples of the raw sample data or 0 for
>>> +       MIDI instruments and synth sounds.  */
>>> +    uint32_t samples;
>>> +
>>> +    /** Sample repeat starting loop point. If looping is enabled, this
>>> +       will be used as restart point.  */
>>> +    uint32_t repeat;
>>> +
>>> +    /** Sample repeat length. End loop point is repeat + rep_len.  */
>>> +    uint32_t rep_len;
>>> +
>>> +    /** Sample repeat count. Some sequencers allow to not only define
>>> +       an infinite repeat count but specify that more precisely.
>>> +       In that case, set this to a non zero value indicating the
>>> +       number of loop counts.  */
>>> +    uint32_t rep_count;
>>> +
>>> +    /** Sample sustain repeat starting loop point. If sustain
>>> looping is
>>> +       enabled, this will be used as sustain restart point.
>>> +       Sustain loop is triggered by a note keyoff event.  */
>>> +    uint32_t sustain_repeat;
>>> +
>>> +    /** Sample sustain repeat length. End sustain loop point is
>>> +       sustain_repeat + sustain_rep_len.  */
>>> +    uint32_t sustain_rep_len;
>>> +
>>> +    /** Sample sustain repeat count. Some sequencers allow to not only
>>> +       define an infinite sustain repeat count but specify that more
>>> +       precisely. In that case, this has to be set to a non-zero value
>>> +       indicating the number of sustain loop counts.  */
>>> +    uint32_t sustain_rep_count;
>>> +
>>> +    /** Sampling rate (frequency) in Hz to play C-4 at which defaults
>>> +       to 8363 (NTSC base frequency used by 60Hz sequencers).  */
>>> +    uint32_t rate;
>>
>>> +    /** Lower sample rate limit (the sample can never exceed this
>>> +       minimum allowed frequency rate during playback).  */
>>> +    uint32_t rate_min;
>>> +
>>> +    /** Upper sample rate limit (the sample can never exceed this
>>> +       maximum allowed frequency rate during playback).  */
>>> +    uint32_t rate_max;
>>
>> Where is this specified? Again, which code _reads_ this values?

> Again, user and/or demuxer choosed values. See my details in song.[ch]
> for this. This is either set by the demuxer and/or by the user if (s)he
> wishes to restrict these values. Defaults are, anyway, no limits, i.e.
> full 32-bit range.

Is there any format that specifies such cutoff?

-Vitor