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    /*
     * This file is part of Libav.
     *
     * Libav 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.
     *
     * Libav 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 Libav; if not, write to the Free Software
     * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
     */
    
    #include "config.h"
    
    #include <fcntl.h>
    #include <unistd.h>
    
    #include <va/va.h>
    #if HAVE_VAAPI_X11
    #   include <va/va_x11.h>
    #endif
    #if HAVE_VAAPI_DRM
    #   include <va/va_drm.h>
    #endif
    
    #include "libavutil/avassert.h"
    #include "libavutil/avconfig.h"
    #include "libavutil/buffer.h"
    #include "libavutil/frame.h"
    #include "libavutil/hwcontext.h"
    #include "libavutil/hwcontext_vaapi.h"
    #include "libavutil/imgutils.h"
    #include "libavutil/opt.h"
    #include "libavutil/pixfmt.h"
    
    #include "libavcodec/vaapi.h"
    
    #include "avconv.h"
    
    
    static AVClass vaapi_class = {
        .class_name = "vaapi",
        .item_name  = av_default_item_name,
        .version    = LIBAVUTIL_VERSION_INT,
    };
    
    #define DEFAULT_SURFACES 20
    
    typedef struct VAAPIDecoderContext {
        const AVClass *class;
    
        AVBufferRef       *device_ref;
        AVHWDeviceContext *device;
        AVBufferRef       *frames_ref;
        AVHWFramesContext *frames;
    
        VAProfile    va_profile;
        VAEntrypoint va_entrypoint;
        VAConfigID   va_config;
        VAContextID  va_context;
    
        enum AVPixelFormat decode_format;
        int decode_width;
        int decode_height;
        int decode_surfaces;
    
        // The output need not have the same format, width and height as the
        // decoded frames - the copy for non-direct-mapped access is actually
        // a whole vpp instance which can do arbitrary scaling and format
        // conversion.
        enum AVPixelFormat output_format;
    
        struct vaapi_context decoder_vaapi_context;
    } VAAPIDecoderContext;
    
    
    static int vaapi_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
    {
        InputStream *ist = avctx->opaque;
        VAAPIDecoderContext *ctx = ist->hwaccel_ctx;
        int err;
    
        err = av_hwframe_get_buffer(ctx->frames_ref, frame, 0);
        if (err < 0) {
            av_log(ctx, AV_LOG_ERROR, "Failed to allocate decoder surface.\n");
        } else {
            av_log(ctx, AV_LOG_DEBUG, "Decoder given surface %#x.\n",
                   (unsigned int)(uintptr_t)frame->data[3]);
        }
        return err;
    }
    
    static int vaapi_retrieve_data(AVCodecContext *avctx, AVFrame *input)
    {
        InputStream *ist = avctx->opaque;
        VAAPIDecoderContext *ctx = ist->hwaccel_ctx;
        AVFrame *output = 0;
        int err;
    
        av_assert0(input->format == AV_PIX_FMT_VAAPI);
    
        if (ctx->output_format == AV_PIX_FMT_VAAPI) {
            // Nothing to do.
            return 0;
        }
    
        av_log(ctx, AV_LOG_DEBUG, "Retrieve data from surface %#x.\n",
               (unsigned int)(uintptr_t)input->data[3]);
    
        output = av_frame_alloc();
        if (!output)
            return AVERROR(ENOMEM);
    
        output->format = ctx->output_format;
    
        err = av_hwframe_transfer_data(output, input, 0);
        if (err < 0) {
            av_log(ctx, AV_LOG_ERROR, "Failed to transfer data to "
                   "output frame: %d.\n", err);
            goto fail;
        }
    
        err = av_frame_copy_props(output, input);
        if (err < 0) {
            av_frame_unref(output);
            goto fail;
        }
    
        av_frame_unref(input);
        av_frame_move_ref(input, output);
        av_frame_free(&output);
    
        return 0;
    
    fail:
        if (output)
            av_frame_free(&output);
        return err;
    }
    
    
    static const struct {
        enum AVCodecID codec_id;
        int codec_profile;
        VAProfile va_profile;
    } vaapi_profile_map[] = {
    #define MAP(c, p, v) { AV_CODEC_ID_ ## c, FF_PROFILE_ ## p, VAProfile ## v }
        MAP(MPEG2VIDEO,  MPEG2_SIMPLE,    MPEG2Simple ),
        MAP(MPEG2VIDEO,  MPEG2_MAIN,      MPEG2Main   ),
        MAP(H263,        UNKNOWN,         H263Baseline),
        MAP(MPEG4,       MPEG4_SIMPLE,    MPEG4Simple ),
        MAP(MPEG4,       MPEG4_ADVANCED_SIMPLE,
                                   MPEG4AdvancedSimple),
        MAP(MPEG4,       MPEG4_MAIN,      MPEG4Main   ),
        MAP(H264,        H264_CONSTRAINED_BASELINE,
                               H264ConstrainedBaseline),
        MAP(H264,        H264_BASELINE,   H264Baseline),
        MAP(H264,        H264_MAIN,       H264Main    ),
        MAP(H264,        H264_HIGH,       H264High    ),
    #if VA_CHECK_VERSION(0, 37, 0)
        MAP(HEVC,        HEVC_MAIN,       HEVCMain    ),
    #endif
        MAP(WMV3,        VC1_SIMPLE,      VC1Simple   ),
        MAP(WMV3,        VC1_MAIN,        VC1Main     ),
        MAP(WMV3,        VC1_COMPLEX,     VC1Advanced ),
        MAP(WMV3,        VC1_ADVANCED,    VC1Advanced ),
        MAP(VC1,         VC1_SIMPLE,      VC1Simple   ),
        MAP(VC1,         VC1_MAIN,        VC1Main     ),
        MAP(VC1,         VC1_COMPLEX,     VC1Advanced ),
        MAP(VC1,         VC1_ADVANCED,    VC1Advanced ),
    #if VA_CHECK_VERSION(0, 35, 0)
        MAP(VP8,         UNKNOWN,       VP8Version0_3 ),
    #endif
    #if VA_CHECK_VERSION(0, 37, 1)
        MAP(VP9,         VP9_0,           VP9Profile0 ),
    #endif
    #undef MAP
    };
    
    static int vaapi_build_decoder_config(VAAPIDecoderContext *ctx,
                                          AVCodecContext *avctx,
                                          int fallback_allowed)
    {
        AVVAAPIDeviceContext *hwctx = ctx->device->hwctx;
        AVVAAPIHWConfig *hwconfig = NULL;
        AVHWFramesConstraints *constraints = NULL;
        VAStatus vas;
        int err, i, j;
        int loglevel = fallback_allowed ? AV_LOG_VERBOSE : AV_LOG_ERROR;
        const AVCodecDescriptor *codec_desc;
        const AVPixFmtDescriptor *pix_desc;
        enum AVPixelFormat pix_fmt;
        VAProfile profile, *profile_list = NULL;
        int profile_count, exact_match, alt_profile;
    
        codec_desc = avcodec_descriptor_get(avctx->codec_id);
        if (!codec_desc) {
            err = AVERROR(EINVAL);
            goto fail;
        }
    
        profile_count = vaMaxNumProfiles(hwctx->display);
        profile_list = av_malloc(profile_count * sizeof(VAProfile));
        if (!profile_list) {
            err = AVERROR(ENOMEM);
            goto fail;
        }
    
        vas = vaQueryConfigProfiles(hwctx->display,
                                    profile_list, &profile_count);
        if (vas != VA_STATUS_SUCCESS) {
            av_log(ctx, loglevel, "Failed to query profiles: %d (%s).\n",
                   vas, vaErrorStr(vas));
            err = AVERROR(EIO);
            goto fail;
        }
    
        profile = VAProfileNone;
        exact_match = 0;
    
        for (i = 0; i < FF_ARRAY_ELEMS(vaapi_profile_map); i++) {
            int profile_match = 0;
            if (avctx->codec_id != vaapi_profile_map[i].codec_id)
                continue;
            if (avctx->profile == vaapi_profile_map[i].codec_profile)
                profile_match = 1;
            profile = vaapi_profile_map[i].va_profile;
            for (j = 0; j < profile_count; j++) {
                if (profile == profile_list[j]) {
                    exact_match = profile_match;
                    break;
                }
            }
            if (j < profile_count) {
                if (exact_match)
                    break;
                alt_profile = vaapi_profile_map[i].codec_profile;
            }
        }
        av_free(profile_list);
    
        if (profile == VAProfileNone) {
            av_log(ctx, loglevel, "No VAAPI support for codec %s.\n",
                   codec_desc->name);
            err = AVERROR(ENOSYS);
            goto fail;
        }
        if (!exact_match) {
            if (fallback_allowed || !hwaccel_lax_profile_check) {
                av_log(ctx, loglevel, "No VAAPI support for codec %s "
                       "profile %d.\n", codec_desc->name, avctx->profile);
                if (!fallback_allowed) {
                    av_log(ctx, AV_LOG_WARNING, "If you want attempt decoding "
                           "anyway with a possibly-incompatible profile, add "
                           "the option -hwaccel_lax_profile_check.\n");
                }
                err = AVERROR(EINVAL);
                goto fail;
            } else {
                av_log(ctx, AV_LOG_WARNING, "No VAAPI support for codec %s "
                       "profile %d: trying instead with profile %d.\n",
                       codec_desc->name, avctx->profile, alt_profile);
                av_log(ctx, AV_LOG_WARNING, "This may fail or give "
                       "incorrect results, depending on your hardware.\n");
            }
        }
    
        ctx->va_profile = profile;
        ctx->va_entrypoint = VAEntrypointVLD;
    
        vas = vaCreateConfig(hwctx->display, ctx->va_profile,
                             ctx->va_entrypoint, 0, 0, &ctx->va_config);
        if (vas != VA_STATUS_SUCCESS) {
            av_log(ctx, AV_LOG_ERROR, "Failed to create decode pipeline "
                   "configuration: %d (%s).\n", vas, vaErrorStr(vas));
            err = AVERROR(EIO);
            goto fail;
        }
    
        hwconfig = av_hwdevice_hwconfig_alloc(ctx->device_ref);
        if (!hwconfig) {
            err = AVERROR(ENOMEM);
            goto fail;
        }
        hwconfig->config_id = ctx->va_config;
    
        constraints = av_hwdevice_get_hwframe_constraints(ctx->device_ref,
                                                          hwconfig);
        if (!constraints)
            goto fail;
    
        // Decide on the decoder target format.
        // If the user specified something with -hwaccel_output_format then
        // try to use that to minimise conversions later.
        ctx->decode_format = AV_PIX_FMT_NONE;
        if (ctx->output_format != AV_PIX_FMT_NONE &&
            ctx->output_format != AV_PIX_FMT_VAAPI) {
            for (i = 0; constraints->valid_sw_formats[i] != AV_PIX_FMT_NONE; i++) {
                if (constraints->valid_sw_formats[i] == ctx->decode_format) {
                    ctx->decode_format = ctx->output_format;
                    av_log(ctx, AV_LOG_DEBUG, "Using decode format %s (output "
                           "format).\n", av_get_pix_fmt_name(ctx->decode_format));
                    break;
                }
            }
        }
        // Otherwise, we would like to try to choose something which matches the
        // decoder output, but there isn't enough information available here to
        // do so.  Assume for now that we are always dealing with YUV 4:2:0, so
        // pick a format which does that.
        if (ctx->decode_format == AV_PIX_FMT_NONE) {
            for (i = 0; constraints->valid_sw_formats[i] != AV_PIX_FMT_NONE; i++) {
                pix_fmt  = constraints->valid_sw_formats[i];
                pix_desc = av_pix_fmt_desc_get(pix_fmt);
                if (pix_desc->nb_components == 3 &&
                    pix_desc->log2_chroma_w == 1 &&
                    pix_desc->log2_chroma_h == 1) {
                    ctx->decode_format = pix_fmt;
                    av_log(ctx, AV_LOG_DEBUG, "Using decode format %s (format "
                           "matched).\n", av_get_pix_fmt_name(ctx->decode_format));
                    break;
                }
            }
        }
        // Otherwise pick the first in the list and hope for the best.
        if (ctx->decode_format == AV_PIX_FMT_NONE) {
            ctx->decode_format = constraints->valid_sw_formats[0];
            av_log(ctx, AV_LOG_DEBUG, "Using decode format %s (first in list).\n",
                   av_get_pix_fmt_name(ctx->decode_format));
            if (i > 1) {
                // There was a choice, and we picked randomly.  Warn the user
                // that they might want to choose intelligently instead.
                av_log(ctx, AV_LOG_WARNING, "Using randomly chosen decode "
                       "format %s.\n", av_get_pix_fmt_name(ctx->decode_format));
            }
        }
    
        // Ensure the picture size is supported by the hardware.
        ctx->decode_width  = avctx->coded_width;
        ctx->decode_height = avctx->coded_height;
        if (ctx->decode_width  < constraints->min_width  ||
            ctx->decode_height < constraints->min_height ||
            ctx->decode_width  > constraints->max_width  ||
            ctx->decode_height >constraints->max_height) {
            av_log(ctx, AV_LOG_ERROR, "VAAPI hardware does not support image "
                   "size %dx%d (constraints: width %d-%d height %d-%d).\n",
                   ctx->decode_width, ctx->decode_height,
                   constraints->min_width,  constraints->max_width,
                   constraints->min_height, constraints->max_height);
            err = AVERROR(EINVAL);
            goto fail;
        }
    
        av_hwframe_constraints_free(&constraints);
        av_freep(&hwconfig);
    
        // Decide how many reference frames we need.  This might be doable more
        // nicely based on the codec and input stream?
        ctx->decode_surfaces = DEFAULT_SURFACES;
        // For frame-threaded decoding, one additional surfaces is needed for
        // each thread.
        if (avctx->active_thread_type & FF_THREAD_FRAME)
            ctx->decode_surfaces += avctx->thread_count;
    
        return 0;
    
    fail:
        av_hwframe_constraints_free(&constraints);
        av_freep(&hwconfig);
        vaDestroyConfig(hwctx->display, ctx->va_config);
        av_free(profile_list);
        return err;
    }
    
    static void vaapi_decode_uninit(AVCodecContext *avctx)
    {
        InputStream *ist = avctx->opaque;
        VAAPIDecoderContext *ctx = ist->hwaccel_ctx;
    
        if (ctx) {
            AVVAAPIDeviceContext *hwctx = ctx->device->hwctx;
    
            if (ctx->va_context != VA_INVALID_ID) {
                vaDestroyContext(hwctx->display, ctx->va_context);
                ctx->va_context = VA_INVALID_ID;
            }
            if (ctx->va_config != VA_INVALID_ID) {
                vaDestroyConfig(hwctx->display, ctx->va_config);
                ctx->va_config = VA_INVALID_ID;
            }
    
            av_buffer_unref(&ctx->frames_ref);
            av_buffer_unref(&ctx->device_ref);
            av_free(ctx);
        }
    
        av_buffer_unref(&ist->hw_frames_ctx);
    
        ist->hwaccel_ctx           = 0;
        ist->hwaccel_uninit        = 0;
        ist->hwaccel_get_buffer    = 0;
        ist->hwaccel_retrieve_data = 0;
    }
    
    int vaapi_decode_init(AVCodecContext *avctx)
    {
        InputStream *ist = avctx->opaque;
        AVVAAPIDeviceContext *hwctx;
        AVVAAPIFramesContext *avfc;
        VAAPIDecoderContext *ctx;
        VAStatus vas;
        int err;
        int loglevel = (ist->hwaccel_id != HWACCEL_VAAPI ? AV_LOG_VERBOSE
                                                         : AV_LOG_ERROR);
    
        if (ist->hwaccel_ctx)
            vaapi_decode_uninit(avctx);
    
        // We have -hwaccel without -vaapi_device, so just initialise here with
        // the device passed as -hwaccel_device (if -vaapi_device was passed, it
        // will always have been called before now).
        if (!hw_device_ctx) {
            err = vaapi_device_init(ist->hwaccel_device);
            if (err < 0)
                return err;
        }
    
        ctx = av_mallocz(sizeof(*ctx));
        if (!ctx)
            return AVERROR(ENOMEM);
        ctx->class = &vaapi_class;
    
        ctx->device_ref = av_buffer_ref(hw_device_ctx);
        ctx->device = (AVHWDeviceContext*)ctx->device_ref->data;
    
        ctx->va_config  = VA_INVALID_ID;
        ctx->va_context = VA_INVALID_ID;
    
        hwctx = ctx->device->hwctx;
    
        ctx->output_format = ist->hwaccel_output_format;
    
        err = vaapi_build_decoder_config(ctx, avctx,
                                         ist->hwaccel_id != HWACCEL_VAAPI);
        if (err < 0) {
            av_log(ctx, loglevel, "No supported configuration for this codec.");
            goto fail;
        }
    
        avctx->pix_fmt = ctx->output_format;
    
        ctx->frames_ref = av_hwframe_ctx_alloc(ctx->device_ref);
        if (!ctx->frames_ref) {
            av_log(ctx, loglevel, "Failed to create VAAPI frame context.\n");
            err = AVERROR(ENOMEM);
            goto fail;
        }
    
        ctx->frames = (AVHWFramesContext*)ctx->frames_ref->data;
    
        ctx->frames->format    = AV_PIX_FMT_VAAPI;
        ctx->frames->sw_format = ctx->decode_format;
        ctx->frames->width     = ctx->decode_width;
        ctx->frames->height    = ctx->decode_height;
        ctx->frames->initial_pool_size = ctx->decode_surfaces;
    
        err = av_hwframe_ctx_init(ctx->frames_ref);
        if (err < 0) {
            av_log(ctx, loglevel, "Failed to initialise VAAPI frame "
                   "context: %d\n", err);
            goto fail;
        }
    
        avfc = ctx->frames->hwctx;
    
        vas = vaCreateContext(hwctx->display, ctx->va_config,
                              ctx->decode_width, ctx->decode_height,
                              VA_PROGRESSIVE,
                              avfc->surface_ids, avfc->nb_surfaces,
                              &ctx->va_context);
        if (vas != VA_STATUS_SUCCESS) {
            av_log(ctx, AV_LOG_ERROR, "Failed to create decode pipeline "
                   "context: %d (%s).\n", vas, vaErrorStr(vas));
            err = AVERROR(EINVAL);
            goto fail;
        }
    
        av_log(ctx, AV_LOG_DEBUG, "VAAPI decoder (re)init complete.\n");
    
        // We would like to set this on the AVCodecContext for use by whoever gets
        // the frames from the decoder, but unfortunately the AVCodecContext we
        // have here need not be the "real" one (H.264 makes many copies for
        // threading purposes).  To avoid the problem, we instead store it in the
        // InputStream and propagate it from there.
        ist->hw_frames_ctx = av_buffer_ref(ctx->frames_ref);
        if (!ist->hw_frames_ctx) {
            err = AVERROR(ENOMEM);
            goto fail;
        }
    
        ist->hwaccel_ctx           = ctx;
        ist->hwaccel_uninit        = vaapi_decode_uninit;
        ist->hwaccel_get_buffer    = vaapi_get_buffer;
        ist->hwaccel_retrieve_data = vaapi_retrieve_data;
    
        ctx->decoder_vaapi_context.display    = hwctx->display;
        ctx->decoder_vaapi_context.config_id  = ctx->va_config;
        ctx->decoder_vaapi_context.context_id = ctx->va_context;
        avctx->hwaccel_context = &ctx->decoder_vaapi_context;
    
        return 0;
    
    fail:
        vaapi_decode_uninit(avctx);
        return err;
    }
    
    static AVClass *vaapi_log = &vaapi_class;
    
    static av_cold void vaapi_device_uninit(AVHWDeviceContext *hwdev)
    {
        AVVAAPIDeviceContext *hwctx = hwdev->hwctx;
        av_log(&vaapi_log, AV_LOG_VERBOSE, "Terminating VAAPI connection.\n");
        vaTerminate(hwctx->display);
    }
    
    av_cold int vaapi_device_init(const char *device)
    {
        AVHWDeviceContext    *hwdev;
        AVVAAPIDeviceContext *hwctx;
        VADisplay display;
        VAStatus vas;
        int major, minor, err;
    
        display = 0;
    
    #if HAVE_VAAPI_X11
        if (!display) {
            Display *x11_display;
    
            // Try to open the device as an X11 display.
            x11_display = XOpenDisplay(device);
            if (!x11_display) {
                av_log(&vaapi_log, AV_LOG_WARNING, "Cannot open X11 display "
                       "%s.\n", XDisplayName(device));
            } else {
                display = vaGetDisplay(x11_display);
                if (!display) {
                    av_log(&vaapi_log, AV_LOG_WARNING, "Cannot open a VA display "
                           "from X11 display %s.\n", XDisplayName(device));
                    XCloseDisplay(x11_display);
                } else {
                    av_log(&vaapi_log, AV_LOG_VERBOSE, "Opened VA display via "
                           "X11 display %s.\n", XDisplayName(device));
                }
            }
        }
    #endif
    
    #if HAVE_VAAPI_DRM
        if (!display && device) {
            int drm_fd;
    
            // Try to open the device as a DRM path.
            drm_fd = open(device, O_RDWR);
            if (drm_fd < 0) {
                av_log(&vaapi_log, AV_LOG_WARNING, "Cannot open DRM device %s.\n",
                       device);
            } else {
                display = vaGetDisplayDRM(drm_fd);
                if (!display) {
                    av_log(&vaapi_log, AV_LOG_WARNING, "Cannot open a VA display "
                           "from DRM device %s.\n", device);
                    close(drm_fd);
                } else {
                    av_log(&vaapi_log, AV_LOG_VERBOSE, "Opened VA display via "
                           "DRM device %s.\n", device);
                }
            }
        }
    #endif
    
        if (!display) {
            av_log(&vaapi_log, AV_LOG_ERROR, "No VA display found for "
                   "device %s.\n", device);
            return AVERROR(EINVAL);
        }
    
        vas = vaInitialize(display, &major, &minor);
        if (vas != VA_STATUS_SUCCESS) {
            av_log(&vaapi_log, AV_LOG_ERROR, "Failed to initialise VAAPI "
                   "connection: %d (%s).\n", vas, vaErrorStr(vas));
            return AVERROR(EIO);
        }
        av_log(&vaapi_log, AV_LOG_VERBOSE, "Initialised VAAPI connection: "
               "version %d.%d\n", major, minor);
    
        hw_device_ctx = av_hwdevice_ctx_alloc(AV_HWDEVICE_TYPE_VAAPI);
        if (!hw_device_ctx) {
            av_log(&vaapi_log, AV_LOG_ERROR, "Failed to create VAAPI "
                   "hardware context.\n");
            vaTerminate(display);
            return AVERROR(ENOMEM);
        }
    
        hwdev = (AVHWDeviceContext*)hw_device_ctx->data;
        hwdev->free = &vaapi_device_uninit;
    
        hwctx = hwdev->hwctx;
        hwctx->display = display;
    
        err = av_hwdevice_ctx_init(hw_device_ctx);
        if (err < 0) {
            av_log(&vaapi_log, AV_LOG_ERROR, "Failed to initialise VAAPI "
                   "hardware context: %d\n", err);
            return err;
        }
    
        return 0;
    }