[FFmpeg-devel] [PATCH 5/8] lavd: add device capabilities API

Lukasz Marek lukasz.m.luki2 at gmail.com
Tue Mar 25 00:39:37 CET 2014


On 22.02.2014 23:33, Lukasz Marek wrote:
> TODO: bump minors, update APIchages
>
> Signed-off-by: Lukasz Marek <lukasz.m.luki at gmail.com>
> ---
>   libavdevice/avdevice.c | 97 ++++++++++++++++++++++++++++++++++++++++++++++++++
>   libavdevice/avdevice.h | 79 ++++++++++++++++++++++++++++++++++++++++
>   libavformat/avformat.h | 36 +++++++++++++++++++
>   3 files changed, 212 insertions(+)
>
> diff --git a/libavdevice/avdevice.c b/libavdevice/avdevice.c
> index 1031afd..911e92b 100644
> --- a/libavdevice/avdevice.c
> +++ b/libavdevice/avdevice.c
> @@ -17,9 +17,46 @@
>    */
>
>   #include "libavutil/avassert.h"
> +#include "libavcodec/avcodec.h"
>   #include "avdevice.h"
>   #include "config.h"
>
> +#define E AV_OPT_FLAG_ENCODING_PARAM
> +#define D AV_OPT_FLAG_DECODING_PARAM
> +#define A AV_OPT_FLAG_AUDIO_PARAM
> +#define V AV_OPT_FLAG_VIDEO_PARAM
> +#define OFFSET(x) offsetof(AVDeviceCapabilitiesQuery, x)
> +
> +const AVOption av_device_capabilities[] = {
> +    { "device_name", "device name", OFFSET(device_name), AV_OPT_TYPE_STRING,
> +        {.str = NULL}, 0, 0, E|D|A|V },
> +    { "codec", "codec", OFFSET(codec), AV_OPT_TYPE_INT,
> +        {.i64 = AV_CODEC_ID_NONE}, AV_CODEC_ID_NONE, INT_MAX, E|D|A|V },
> +    { "format", "format", OFFSET(format), AV_OPT_TYPE_INT,
> +        {.i64 = -1}, -1, INT_MAX, E|D|A|V },
> +
> +    { "sample_rate", "sample rate", OFFSET(sample_rate), AV_OPT_TYPE_INT,
> +        {.i64 = -1}, -1, INT_MAX, E|D|A },
> +    { "channels", "channels", OFFSET(channels), AV_OPT_TYPE_INT,
> +        {.i64 = -1}, -1, INT_MAX, E|D|A },
> +    { "channel_layout", "channel layout", OFFSET(channel_layout), AV_OPT_TYPE_INT64,
> +        {.i64 = -1}, -1, INT_MAX, E|D|A },
> +
> +    { "window_size", "window size", OFFSET(window_width), AV_OPT_TYPE_IMAGE_SIZE,
> +        {.str = NULL}, -1, INT_MAX, E|D|V },
> +    { "frame_size", "frame size", OFFSET(frame_width), AV_OPT_TYPE_IMAGE_SIZE,
> +        {.str = NULL}, -1, INT_MAX, E|D|V },
> +    { "fps", "fps", OFFSET(fps), AV_OPT_TYPE_RATIONAL,
> +        {.dbl = -1}, -1, INT_MAX, E|D|V },
> +    { NULL }
> +};
> +
> +#undef E
> +#undef D
> +#undef A
> +#undef V
> +#undef OFFSET
> +
>   unsigned avdevice_version(void)
>   {
>       av_assert0(LIBAVDEVICE_VERSION_MICRO >= 100);
> @@ -93,6 +130,66 @@ int avdevice_dev_to_app_control_message(struct AVFormatContext *s, enum AVDevToA
>       return s->control_message_cb(s, type, data, data_size);
>   }
>
> +int avdevice_capabilities_create(AVDeviceCapabilitiesQuery **caps, AVFormatContext *s,
> +                                 AVDictionary **device_options)
> +{
> +    int ret;
> +    av_assert0(s && caps);
> +    av_assert0(s->iformat || s->oformat);
> +    if ((s->oformat && !s->oformat->create_device_capabilities) ||
> +        (s->iformat && !s->iformat->create_device_capabilities))
> +        return AVERROR(ENOSYS);
> +    *caps = av_mallocz(sizeof(**caps));
> +    if (!(*caps))
> +        return AVERROR(ENOMEM);
> +    (*caps)->device_context = s;
> +    if (device_options && ((ret = av_opt_set_dict(s->priv_data, device_options)) < 0))
> +        goto fail;
> +    if (s->iformat) {
> +        if ((ret = s->iformat->create_device_capabilities(s, *caps)) < 0)
> +            goto fail;
> +    } else {
> +        if ((ret = s->oformat->create_device_capabilities(s, *caps)) < 0)
> +            goto fail;
> +    }
> +    av_opt_set_defaults(*caps);
> +    return 0;
> +  fail:
> +    av_freep(caps);
> +    return ret;
> +}
> +
> +int avdevice_capabilities_apply(AVDeviceCapabilitiesQuery *caps, AVFormatContext *s,
> +                               enum AVDeviceCapabilitiesApplyStrategy strategy)
> +{
> +    av_assert0(s);
> +    av_assert0(s->iformat || s->oformat);
> +    if (s->iformat) {
> +        if (!s->iformat->apply_device_capabilities)
> +            return AVERROR(ENOSYS);
> +        return s->iformat->apply_device_capabilities(s, caps, strategy);
> +    }
> +    if (!s->oformat->apply_device_capabilities)
> +        return AVERROR(ENOSYS);
> +    return s->oformat->apply_device_capabilities(s, caps, strategy);
> +}
> +
> +void avdevice_capabilities_free(AVDeviceCapabilitiesQuery **caps, AVFormatContext *s)
> +{
> +    if (!s || !caps || !(*caps))
> +        return;
> +    av_assert0(s->iformat || s->oformat);
> +    if (s->iformat) {
> +        if (s->iformat->free_device_capabilities)
> +            s->iformat->free_device_capabilities(s, *caps);
> +    } else {
> +        if (s->oformat->free_device_capabilities)
> +            s->oformat->free_device_capabilities(s, *caps);
> +    }
> +    av_free((*caps)->device_name);
> +    av_freep(caps);
> +}
> +
>   int avdevice_list_devices(AVFormatContext *s, AVDeviceInfoList **device_list)
>   {
>       av_assert0(s);
> diff --git a/libavdevice/avdevice.h b/libavdevice/avdevice.h
> index 47bf8f4..708ef65 100644
> --- a/libavdevice/avdevice.h
> +++ b/libavdevice/avdevice.h
> @@ -43,6 +43,9 @@
>    * @}
>    */
>
> +#include "libavutil/log.h"
> +#include "libavutil/opt.h"
> +#include "libavutil/dict.h"
>   #include "libavformat/avformat.h"
>
>   /**
> @@ -208,6 +211,82 @@ int avdevice_dev_to_app_control_message(struct AVFormatContext *s,
>                                           void *data, size_t data_size);
>
>   /**
> + * Structure describes device settings.
> + *
> + * It is used by devices in conjuntion with av_device_capabilities AVOption table
> + * to to implement capabilities probing API based on AVOption API.
> + */
> +typedef struct AVDeviceCapabilitiesQuery {
> +    const AVClass *class;
> +    char *device_name;
> +    AVFormatContext *device_context;
> +    enum AVCodecID codec;
> +    int format;                          /**< AVSampleFormat or AVPixelFormat */
> +    int sample_rate;
> +    int channels;
> +    int64_t channel_layout;
> +    int window_width;
> +    int window_height;
> +    int frame_width;
> +    int frame_height;
> +    AVRational fps;
> +} AVDeviceCapabilitiesQuery;
> +
> +extern const AVOption av_device_capabilities[];
> +
> +enum AVDeviceCapabilitiesApplyStrategy {
> +    AVDEVICE_STRATEGY_APPLY_IF_VALID,                /**< apply settings when valid */
> +    AVDEVICE_STRATEGY_FIX_TO_THE_NEAREST,            /**< adjust structure only to the nearest valid value */
> +    AVDEVICE_STRATEGY_FIX_TO_THE_BEST,               /**< adjust structure only to the best valid value */
> +    AVDEVICE_STRATEGY_FIX_TO_THE_NEAREST_AND_APPLY,  /**< adjust values to the nearest valid value and apply */
> +    AVDEVICE_STRATEGY_FIX_TO_THE_BEST_AND_APPLY      /**< adjust values to the best valid value and apply */
> +};
> +
> +/**
> + * Initialize capabilities probing API based on AVOption API.
> + *
> + * avdevice_capabilities_free() must be called when query capabilities API is
> + * not used anymore.
> + *
> + * @note: It is not allowed to free device context before calling avdevice_capabilities_free().
> + *
> + * @param caps           device configuration
> + * @param s              device context
> + * @param device_options device options
> + * @return >= 0 on success, negative otherwise.
> + */
> +int avdevice_capabilities_create(AVDeviceCapabilitiesQuery **caps, AVFormatContext *s,
> +                                 AVDictionary **device_options);
> +
> +/**
> + * Apply set parameters to device context and release data allocated
> + * by avdevice_init_device_capabilities().
> + *
> + * All set capabilities are validated and tested. When configuration is not
> + * valid then adjustment takes place according to provided strategy.
> + * When it is required by provided strategy, set capabilities are applied into
> + * device context. Mapping between capablities and device settings are device-specific.
> + * In particular output device may not apply all parameters to the context,
> + * but use stream properties when avformat_write_header() is called.
> + *
> + * @param caps     device configuration
> + * @param s        device context
> + * @param strategy apply strategy
> + * @return 0 when configuration is not applied, 1 when configuration is applied,
> + *         negative on error.
> + */
> +int avdevice_capabilities_apply(AVDeviceCapabilitiesQuery *caps, AVFormatContext *s,
> +                                enum AVDeviceCapabilitiesApplyStrategy strategy);
> +
> +/**
> + * Free resources created by avdevice_capabilities_create()
> + *
> + * @param caps device configuration
> + * @param s    device context
> + */
> +void avdevice_capabilities_free(AVDeviceCapabilitiesQuery **caps, AVFormatContext *s);
> +
> +/**
>    * Structure describes basic parameters of the device.
>    */
>   typedef struct AVDeviceInfo {
> diff --git a/libavformat/avformat.h b/libavformat/avformat.h
> index 52eeb61..e2d36f6 100644
> --- a/libavformat/avformat.h
> +++ b/libavformat/avformat.h
> @@ -262,6 +262,7 @@
>   struct AVFormatContext;
>
>   struct AVDeviceInfoList;
> +struct AVDeviceCapabilitiesQuery;
>
>   /**
>    * @defgroup metadata_api Public Metadata API
> @@ -531,6 +532,22 @@ typedef struct AVOutputFormat {
>        * @see avdevice_list_devices() for more details.
>        */
>       int (*get_device_list)(struct AVFormatContext *s, struct AVDeviceInfoList *device_list);
> +    /**
> +     * Initialize device capabilities submodule.
> +     * @see avdevice_capabilities_create() for more details.
> +     */
> +    int (*create_device_capabilities)(struct AVFormatContext *s, struct AVDeviceCapabilitiesQuery *caps);
> +    /**
> +     * Apply currently set device capabilities to device context.
> +     * @see avdevice_capabilities_apply() for more details.
> +     */
> +    int (*apply_device_capabilities)(struct AVFormatContext *s,
> +                                     struct AVDeviceCapabilitiesQuery *caps, int strategy);
> +    /**
> +     * Free device capabilities submodule.
> +     * @see avdevice_capabilities_free() for more details.
> +     */
> +    int (*free_device_capabilities)(struct AVFormatContext *s, struct AVDeviceCapabilitiesQuery *caps);
>   } AVOutputFormat;
>   /**
>    * @}
> @@ -665,6 +682,25 @@ typedef struct AVInputFormat {
>        * @see avdevice_list_devices() for more details.
>        */
>       int (*get_device_list)(struct AVFormatContext *s, struct AVDeviceInfoList *device_list);
> +
> +    /**
> +     * Initialize device capabilities submodule.
> +     * @see avdevice_capabilities_create() for more details.
> +     */
> +    int (*create_device_capabilities)(struct AVFormatContext *s, struct AVDeviceCapabilitiesQuery *caps);
> +
> +    /**
> +     * Apply currently set device capabilities to device context.
> +     * @see avdevice_capabilities_apply() for more details.
> +     */
> +    int (*apply_device_capabilities)(struct AVFormatContext *s,
> +                                     struct AVDeviceCapabilitiesQuery *caps, int strategy);
> +
> +    /**
> +     * Free device capabilities submodule.
> +     * @see avdevice_capabilities_free() for more details.
> +     */
> +    int (*free_device_capabilities)(struct AVFormatContext *s, struct AVDeviceCapabilitiesQuery *caps);
>   } AVInputFormat;
>   /**
>    * @}
>


AVOptionRanges issue took long, no comments for this one, can I assume 
it is OK?



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